Here's an idea. Why not blame anyone at all? He's turning 38, which is alot for a striker. Him leaving would've had to have been either now, next season or at the very most the next season after that.
First option = The perfect ending with him lifting the trophy on his final day.
Second option = He wouldn't feature much, maybe just a handful of minutes.
Third option = He wouldn't feature at all. Yes, it's Del Piero, but if you're pushing 40, as a striker, I don't think you're gonna see any playing time at Juventus, no matter who you are.
Gutted that he won't be part of our team anymore, but I'm so happy for the fact that, 1 year from now, 5 years from now, 20 years from now, my final memories of Del Piero will be of that big smile on his face, holding the trophy aloft!