Angular default provider in Module

I have the following example. The idea is to have a default implementation for ActionsServiceBase eg. ActionServiceDefault when any implementation of the abstract class is not provided. For some reason, it doesn't work. Is it technically possible to provide a fallback provider like in the example? I added ActionServiceCustom to the providers array with useExisting as a double check - I am aware it shouldn't be necessary if providedIn: "root" is present in class definition. I know I can workaround it using forRoot() pattern but I intentionally don't want to go this way since we consider migration from modules to standalone in the future.

@Injectable()
export abstract class ActionsServiceBase {
abstract isRenewing(): boolean;
}

@Injectable()
export class ActionServiceDefault extends ActionsServiceBase {
isRenewing() {
console.log('ActionServiceDefault');
return true;
}
}

@Injectable({
providedIn: 'root',
})
export class ActionServiceCustom extends ActionsServiceBase {
isRenewing() {
console.log('ActionServiceCustom');
return true;
}
}

@NgModule({
providers: [
{
provide: ActionsServiceBase,
useFactory: (injector: Injector) => {
try {
return injector.get(ActionsServiceBase);
} catch {
// Return the default implementation if not found
console.error('no impl found');
return new ActionServiceDefault();
}
},
deps: [INJECTOR],
},
],
})
export class CustomModule {}

bootstrapApplication(App, {
providers: [
{
provide: ActionsServiceBase,
useExisting: ActionServiceCustom,
},
importProvidersFrom(CustomModule),
],
});

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