We're fortunate that we're just 2 games into the season where we all can hope and pray the staff can teach some of these terrible habits out of him, and he can somehow learn to reduce the urge of doing the wrong things he keeps on doing.
He does a lot of very good things and is productive when he's on the floor.
One thing the staff could try, which I've seen in the past, is to bring a foul prone players off the bench instead of starting them. Let the refs get those early quick whistles out of their system on other players and also give the coaching staff the opportunity to see how the refs are officiating the game and instructing SJ on how aggressive he can be. That's not to say he'll actually be able to follow those instructions, but it might help reduce his nightly foul numbers by 1 which might help to keep him on the floor a little longer.
The one downside to that is it does impact the rotations and he does some things that Reed is either still learning and/or is not as good at. Maybe bringing him off the bench can also be that change of pace dynamic that Hurley liked and spoke about in the past. SJ and Diarra are both sort of energizer bunnies that might provide greater overall value coming off the bench. DH seems to have made that decision with Hass with Mahaney starting. The one downside to that is you always want to come out of the gate fast (as in productive), and having your best combination of players on the floor to start the game is usually the preferred way to go. Both Reed and Mahaney seemed to have slow starts (first halves) so starting with both might has its downside. Though now is a good time to try things out.
I'd sit SJ next to one of the assistant coaches at the start of the game who can talk through how he should defend in the situations taking place. Then put him in after a few minutes and hope he can execute what he is being taught. Regardless how they go about it, they somehow have to get things through to him so that he can stay on the floor longer. We know Danny and the staff are well aware of this, and will try what they can to coach these bad habits out of him. Lots of games and learning experiences to go. I'm hoping he improves as the season goes on.
He does seem to get 1 or 2 bad calls against him in many games, which seems to happen with bigs that have not built reputation of being able to play aggressively without fouling. He has this herky-jerky way about his game that I think influences the refs. I wonder if he would be better off trying to defend in a more smooth manner and learn to explode at the right time. He is an explosive athlete but tends to look kind of jumpy which might be part of the reason why he gets some of these marginal calls. With that said, he also seems to pick up over aggressive and mental error type of fouls (reaching in, playing too aggressive far from the basket, jumping into players too aggressively around the basket, etc.). These type of mental mistakes not only result in fouls, but sometimes put him out of position. I hope he can correct these things for his sake and the sake of the team.