diff --git a/api_guard/dist/types/index.d.ts b/api_guard/dist/types/index.d.ts
index 7cfc595493..1a14efdf38 100644
--- a/api_guard/dist/types/index.d.ts
+++ b/api_guard/dist/types/index.d.ts
@@ -108,8 +108,8 @@ export declare function concatMap<T, O extends ObservableInput<any>>(project: (v
 export declare function concatMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined): OperatorFunction<T, ObservedValueOf<O>>;
 export declare function concatMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
-export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<any, ObservedValueOf<O>>;
-export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<any, ObservedValueOf<O>>;
+export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
+export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<unknown, ObservedValueOf<O>>;
 export declare function concatMapTo<T, R, O extends ObservableInput<unknown>>(observable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
 export declare function concatWith<T, A extends readonly unknown[]>(...otherSources: [...ObservableInputTuple<A>]): OperatorFunction<T, T | A[number]>;
@@ -314,7 +314,7 @@ export declare type Head<X extends readonly any[]> = ((...args: X) => any) exten
 
 export declare function identity<T>(x: T): T;
 
-export declare function ignoreElements(): OperatorFunction<any, never>;
+export declare function ignoreElements(): OperatorFunction<unknown, never>;
 
 export declare function iif<T, F>(condition: () => boolean, trueResult: ObservableInput<T>, falseResult: ObservableInput<F>): Observable<T | F>;
 
@@ -340,7 +340,7 @@ export declare function lastValueFrom<T>(source: Observable<T>): Promise<T>;
 export declare function map<T, R>(project: (value: T, index: number) => R): OperatorFunction<T, R>;
 export declare function map<T, R, A>(project: (this: A, value: T, index: number) => R, thisArg: A): OperatorFunction<T, R>;
 
-export declare function mapTo<R>(value: R): OperatorFunction<any, R>;
+export declare function mapTo<R>(value: R): OperatorFunction<unknown, R>;
 export declare function mapTo<T, R>(value: R): OperatorFunction<T, R>;
 
 export declare function materialize<T>(): OperatorFunction<T, Notification<T> & ObservableNotification<T>>;
@@ -358,7 +358,7 @@ export declare function mergeMap<T, O extends ObservableInput<any>>(project: (va
 export declare function mergeMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined, concurrent?: number): OperatorFunction<T, ObservedValueOf<O>>;
 export declare function mergeMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R, concurrent?: number): OperatorFunction<T, R>;
 
-export declare function mergeMapTo<O extends ObservableInput<unknown>>(innerObservable: O, concurrent?: number): OperatorFunction<any, ObservedValueOf<O>>;
+export declare function mergeMapTo<O extends ObservableInput<unknown>>(innerObservable: O, concurrent?: number): OperatorFunction<unknown, ObservedValueOf<O>>;
 export declare function mergeMapTo<T, R, O extends ObservableInput<unknown>>(innerObservable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R, concurrent?: number): OperatorFunction<T, R>;
 
 export declare function mergeScan<T, R>(accumulator: (acc: R, value: T, index: number) => ObservableInput<R>, seed: R, concurrent?: number): OperatorFunction<T, R>;
@@ -729,8 +729,8 @@ export declare function switchMap<T, O extends ObservableInput<any>>(project: (v
 export declare function switchMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined): OperatorFunction<T, ObservedValueOf<O>>;
 export declare function switchMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
-export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<any, ObservedValueOf<O>>;
-export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<any, ObservedValueOf<O>>;
+export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
+export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<unknown, ObservedValueOf<O>>;
 export declare function switchMapTo<T, R, O extends ObservableInput<unknown>>(observable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
 export declare function switchScan<T, R, O extends ObservableInput<any>>(accumulator: (acc: R, value: T, index: number) => O, seed: R): OperatorFunction<T, ObservedValueOf<O>>;
diff --git a/api_guard/dist/types/operators/index.d.ts b/api_guard/dist/types/operators/index.d.ts
index 034286c140..4d673c5b08 100644
--- a/api_guard/dist/types/operators/index.d.ts
+++ b/api_guard/dist/types/operators/index.d.ts
@@ -45,8 +45,8 @@ export declare function concatMap<T, O extends ObservableInput<any>>(project: (v
 export declare function concatMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined): OperatorFunction<T, ObservedValueOf<O>>;
 export declare function concatMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
-export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<any, ObservedValueOf<O>>;
-export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<any, ObservedValueOf<O>>;
+export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
+export declare function concatMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<unknown, ObservedValueOf<O>>;
 export declare function concatMapTo<T, R, O extends ObservableInput<unknown>>(observable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
 export declare function concatWith<T, A extends readonly unknown[]>(...otherSources: [...ObservableInputTuple<A>]): OperatorFunction<T, T | A[number]>;
@@ -144,7 +144,7 @@ export interface GroupByOptionsWithElement<K, E, T> {
     element: (value: T) => E;
 }
 
-export declare function ignoreElements(): OperatorFunction<any, never>;
+export declare function ignoreElements(): OperatorFunction<unknown, never>;
 
 export declare function isEmpty<T>(): OperatorFunction<T, boolean>;
 
@@ -157,7 +157,7 @@ export declare function last<T, D = T>(predicate: (value: T, index: number, sour
 export declare function map<T, R>(project: (value: T, index: number) => R): OperatorFunction<T, R>;
 export declare function map<T, R, A>(project: (this: A, value: T, index: number) => R, thisArg: A): OperatorFunction<T, R>;
 
-export declare function mapTo<R>(value: R): OperatorFunction<any, R>;
+export declare function mapTo<R>(value: R): OperatorFunction<unknown, R>;
 export declare function mapTo<T, R>(value: R): OperatorFunction<T, R>;
 
 export declare function materialize<T>(): OperatorFunction<T, Notification<T> & ObservableNotification<T>>;
@@ -175,7 +175,7 @@ export declare function mergeMap<T, O extends ObservableInput<any>>(project: (va
 export declare function mergeMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined, concurrent?: number): OperatorFunction<T, ObservedValueOf<O>>;
 export declare function mergeMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R, concurrent?: number): OperatorFunction<T, R>;
 
-export declare function mergeMapTo<O extends ObservableInput<unknown>>(innerObservable: O, concurrent?: number): OperatorFunction<any, ObservedValueOf<O>>;
+export declare function mergeMapTo<O extends ObservableInput<unknown>>(innerObservable: O, concurrent?: number): OperatorFunction<unknown, ObservedValueOf<O>>;
 export declare function mergeMapTo<T, R, O extends ObservableInput<unknown>>(innerObservable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R, concurrent?: number): OperatorFunction<T, R>;
 
 export declare function mergeScan<T, R>(accumulator: (acc: R, value: T, index: number) => ObservableInput<R>, seed: R, concurrent?: number): OperatorFunction<T, R>;
@@ -300,8 +300,8 @@ export declare function switchMap<T, O extends ObservableInput<any>>(project: (v
 export declare function switchMap<T, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: undefined): OperatorFunction<T, ObservedValueOf<O>>;
 export declare function switchMap<T, R, O extends ObservableInput<any>>(project: (value: T, index: number) => O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
-export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<any, ObservedValueOf<O>>;
-export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<any, ObservedValueOf<O>>;
+export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
+export declare function switchMapTo<O extends ObservableInput<unknown>>(observable: O, resultSelector: undefined): OperatorFunction<unknown, ObservedValueOf<O>>;
 export declare function switchMapTo<T, R, O extends ObservableInput<unknown>>(observable: O, resultSelector: (outerValue: T, innerValue: ObservedValueOf<O>, outerIndex: number, innerIndex: number) => R): OperatorFunction<T, R>;
 
 export declare function switchScan<T, R, O extends ObservableInput<any>>(accumulator: (acc: R, value: T, index: number) => O, seed: R): OperatorFunction<T, ObservedValueOf<O>>;
diff --git a/src/internal/operators/concatMapTo.ts b/src/internal/operators/concatMapTo.ts
index 0fd8b253a9..b7503c3b9f 100644
--- a/src/internal/operators/concatMapTo.ts
+++ b/src/internal/operators/concatMapTo.ts
@@ -3,12 +3,12 @@ import { ObservableInput, OperatorFunction, ObservedValueOf } from '../types';
 import { isFunction } from '../util/isFunction';
 
 /* tslint:disable:max-line-length */
-export function concatMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<any, ObservedValueOf<O>>;
+export function concatMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
 /** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
 export function concatMapTo<O extends ObservableInput<unknown>>(
   observable: O,
   resultSelector: undefined
-): OperatorFunction<any, ObservedValueOf<O>>;
+): OperatorFunction<unknown, ObservedValueOf<O>>;
 /** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
 export function concatMapTo<T, R, O extends ObservableInput<unknown>>(
   observable: O,
diff --git a/src/internal/operators/ignoreElements.ts b/src/internal/operators/ignoreElements.ts
index 4b85c9c27d..2663f7ff18 100644
--- a/src/internal/operators/ignoreElements.ts
+++ b/src/internal/operators/ignoreElements.ts
@@ -38,7 +38,7 @@ import { noop } from '../util/noop';
  * `complete` or `error`, based on which one is called by the source
  * Observable.
  */
-export function ignoreElements(): OperatorFunction<any, never> {
+export function ignoreElements(): OperatorFunction<unknown, never> {
   return operate((source, subscriber) => {
     source.subscribe(new OperatorSubscriber(subscriber, noop));
   });
diff --git a/src/internal/operators/mapTo.ts b/src/internal/operators/mapTo.ts
index 0f8c72a1ec..1caab7eac3 100644
--- a/src/internal/operators/mapTo.ts
+++ b/src/internal/operators/mapTo.ts
@@ -1,7 +1,7 @@
 import { OperatorFunction } from '../types';
 import { map } from './map';
 
-export function mapTo<R>(value: R): OperatorFunction<any, R>;
+export function mapTo<R>(value: R): OperatorFunction<unknown, R>;
 /** @deprecated Do not specify explicit type parameters. Signatures with type parameters that cannot be inferred will be removed in v8. */
 export function mapTo<T, R>(value: R): OperatorFunction<T, R>;
 
@@ -37,6 +37,6 @@ export function mapTo<T, R>(value: R): OperatorFunction<T, R>;
  * @return A function that returns an Observable that emits the given `value`
  * every time the source Observable emits.
  */
-export function mapTo<R>(value: R): OperatorFunction<any, R> {
+export function mapTo<R>(value: R): OperatorFunction<unknown, R> {
   return map(() => value);
 }
diff --git a/src/internal/operators/mergeMapTo.ts b/src/internal/operators/mergeMapTo.ts
index 28849a2669..4a2eeeedbf 100644
--- a/src/internal/operators/mergeMapTo.ts
+++ b/src/internal/operators/mergeMapTo.ts
@@ -6,7 +6,7 @@ import { isFunction } from '../util/isFunction';
 export function mergeMapTo<O extends ObservableInput<unknown>>(
   innerObservable: O,
   concurrent?: number
-): OperatorFunction<any, ObservedValueOf<O>>;
+): OperatorFunction<unknown, ObservedValueOf<O>>;
 /** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
 export function mergeMapTo<T, R, O extends ObservableInput<unknown>>(
   innerObservable: O,
diff --git a/src/internal/operators/switchMapTo.ts b/src/internal/operators/switchMapTo.ts
index a3ff875fe9..1436204f70 100644
--- a/src/internal/operators/switchMapTo.ts
+++ b/src/internal/operators/switchMapTo.ts
@@ -3,12 +3,12 @@ import { ObservableInput, OperatorFunction, ObservedValueOf } from '../types';
 import { isFunction } from '../util/isFunction';
 
 /* tslint:disable:max-line-length */
-export function switchMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<any, ObservedValueOf<O>>;
+export function switchMapTo<O extends ObservableInput<unknown>>(observable: O): OperatorFunction<unknown, ObservedValueOf<O>>;
 /** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
 export function switchMapTo<O extends ObservableInput<unknown>>(
   observable: O,
   resultSelector: undefined
-): OperatorFunction<any, ObservedValueOf<O>>;
+): OperatorFunction<unknown, ObservedValueOf<O>>;
 /** @deprecated The `resultSelector` parameter will be removed in v8. Use an inner `map` instead. Details: https://rxjs.dev/deprecations/resultSelector */
 export function switchMapTo<T, R, O extends ObservableInput<unknown>>(
   observable: O,