How to create a modified version of the Angular @Optional() decorator that returns a default/fallback value

As the following feature request for Angular is still open I'd "simply" like to create my own version of the @Optional() decorator that can take/return a default value in case the injected property has not been provided: https://github.com/angular/angular/issues/25395

I would like to avoid the following:

export class ExampleComponent{
  constructor(
    @Optional() private exampleService?: ExampleService
  ) {
    if (!this.exampleService) {
      this.exampleService = new FallbackExampleService();
    }
}

Instead I'd like to write something like this:

export class ExampleComponent{
  constructor(
    @OptionalWithDefault(new FallbackExampleService()) private exampleService: ExampleService
  ) {}
}

Unfortunately the original code inside the Angular project in my eyes is not that easy to follow. You can find it here: https://github.com/angular/angular/blob/main/packages/core/src/di/metadata.ts#L105

and its underlying method makeParamDecorator() here: https://github.com/angular/angular/blob/main/packages/core/src/util/decorators.ts#L99

Has maybe anyone of you already done something similar?