mandzukic and cuadrado are well over 30, of course they will start to regress at some point, but i doubt they had a dislike towards allegri (as you claimed). btw both of them had injuries, and mandzukic had a very strong first half of the season alongside cr. dybala progressed for 3 years that you generously forgot. morata regressed under sarri. etc...
some attacking posters on tuz regressed under allegri, i give you that.