Angular 10: subscribing to an observable won't fire after a next call

Question

I have a very simple scenario of subscribing to an Observable via an injected FooService:

foo.service.ts:

@Injectable()
export class FooService {    
    private foosSubject = new Subject<FooModelDTO[]>();        
    
    constructor() {
      this.setFoos([{id: "Some Id"}]);
    }
    setFoos(foos) {
        console.log("FooService.setFoos", foos);
        this.foosSubject.next(foos);
    }

    onFoos(): Observable<FooModelDTO[]> {
        return this.foosSubject.asObservable();
    }    
}

app.componenet.ts:

export class AppComponent  {
    private fooSubscription: Subscription;
    constructor(private _fooService: FooService) { 
      this.fooSubscription = this._fooService.onFoos()
      .subscribe({
        next: this.handleSubscription.bind(this)
      });      
    }

    handleSubscription(foosModels: FooModelDTO[]) {
        console.log("Yes!!!!"); <--- I'm not getting here!
    }
}

My question:

Why I'm am not able to fire the handleSubscription method via subscribe's next?

StackBlitz