I get your point but i did kind of mentioned it in "winning ways" as in for example shortly after mid-season let's say Conte already had a strong enough word/view on who he will play and who not, doubt the board wasn't already convinced enough of his capabilities to take his assesments serious even before the Scudetto was won..
Did also a follow-up post to that where i think i've detailed it a bit better on what i think the most likely scenario might've been behind the scenes.
Conte probably pushed for it while Agnelli & co obviously facilitated it.
Most likely pushed for it by not guaranteeing ADP any decent playing time while also making him seem as an misfit both physically and tactically to Agnelli/management whom eventually facilitated the divorce without intervening in any way over the coach's assessment... IMO everyone at the time believed in Conte's system so truth be told i doubt anyone would contradict him over tactical decisions or the way he handled the players at his disposal, especially even more so after making us look again relevant as a team.
The disrespect and lack of support from Agnelli & co at the time is what probably kept Del Piero away for this long, while in all fairness there's also the emotional factor that could also be playing a big part in him not attending any games at the J stadium ever since.
Anyway, it's just speculation afterall, IMO it's likely a bit of everything if we look at it without bias, however what i believe everyone can agree on is that both Agnelli and Conte had an important say in his departure at the time, while one probably weighted more on it than the other.