Havertz is great and will get even better. He’s been given time and support from Tuchel.
Pulisic has great talent but would’ve performed better if he had the faith of the manager. Tuchel immediately considered him as a bench player ignoring his previous performances under Lampard (where he could’ve been the club POTY). He’s still put in some top performances, but has unsurprisingly been inconsistent. Hope he moves on to be great somewhere else.
Ziyech has just started to come good after having difficulty with the way Tuchel wanted him to play. Maybe there’ll be more from him next season.
Are Pulisic and Ziyech’s performances the result of Tuchel’s management? I would say largely yes. Overall he’s won trophies so it’s the price to pay.