I'm guessing he is really happy to be away from Carlisle's restrictive coaching. Gentry let Boogie and AD cook in NO, so I think you are right in that a lot of Sabonis' potential is about to be realized.
The general knock on Alvin Gentry has always been that while he's a great offensive coach, he's quite possibly the worst defensive coach in league history (he somehow had a team featuring AD and Jrue at the bottom of the defensive rankings every season).
Players absolutely seem to love playing for him (I seem to remember AD even specifying that his issue wasn't with Gentry when he was burning all his bridges in NO) and his offenses are always generally free-flowing variations of the Suns 7 seconds or less offense that then got adapted into the Warriors high post system under Kerr. The thing is that Gentry has never had a big with the court vision of Sabonis before. AD, while a better passer than he gets credit for, is general not great with the offense flowing through him and Zion was a rookie. The half season before Boogie blew out his Achilles though, Gentry had him putting up 25/13/5.5. They also had the fastest pace in the league, which in hindsight probably helped cause Boogie's injury and is probably unsustainable for a team running out two seven footers at once.
Alvin's a smart offensive coach and I have no doubt that he'll be able to adjust his style to Sabonis, who finally gets to play in an offense that isn't coached by Nate McMillan or uptight sycophants obsessed with running systems that don't fit their personnel.
I just hope that Monte adding solid defensive players is enough to keep us from being absolutely horrible on that end for the rest of the year.