His body was beat to hell. It's unfair to just blame it on overeating.
Hell, he already had back issues before he even got drafted and his body certainly let him down over the course of his short career. Know he had foot issues too.
A variety of factors led him to being out of the league by 30.
I suppose you can argue that back and foot injuries are to be expected when you're carrying extra weight. But yeah, his body just wasn't as durable as some other big guys.
In terms of eating, at least in Sully's case, it's going to get viewed as one of two ways: he was a guy who lacked willpower and discipline, or he's a guy who struggled with legitimate addiction issues. I tend to be a bit sympathetic on these issues, and will say that based upon the tens of millions of people who fail at dieting, there's an addictive factor there.
I think Sully tried a private chef. I'm not sure how that went. I remember he weighed over 300 pounds at some point, so whatever diet he was on, there was obviously some sort of relapse.
But, even if Sully could control his weight, he'd still have to shake the domestic abuser label. I think that's a hard hurdle for NBA teams to accept, even when there's a dismissal of charges.