It would vacate his conviction and get him out of prison. His life after may not be great, but he still has money.
As for his future career, people tend to forget/ignore all of that anyway. Chris Brown savagely beat Rihanna nearly to death, and he still has no problems booking a tour. But even if it was still a thing, he’d just say (accurately, mind you) that it was all just a plan by his lawyers. It was the most effective way of getting him out of prison, and clearing his record.