I want him to stay. Asking for a transfer is exactly what Agnelli would want. Ale won't do that.
He's not stupid to do it.
If they don't want him, he'll be out in 6 months. Asking for a transfer will make it look like he's bitching for not getting playing minutes and it will leave a dark mark on his Juve career. 6 months is nothing. If he goes to the USA, where the season starts in March (?) that's actually only 3 months, not even 6.
Staying in Juve means that he gets a chance to lift a trophy, get a farewell match and it gives him a challenge to fight for a spot in the team. Leaving Juve for US soccer only gives him 3 more months of playing time.
He definitely won't ask for a transfer in January.