Why do people hate Sullinger so much? Guy has played well for us. Yes, he struggles with his weight. It's his body type. It ain't easy given his metabolism.
I don't know where to blame but he does have lows. People don't give him credit for his highs enough (good rebounding, sometimes quite good on offense, strong passer) but I think the last two seasons he has looked awful at the end of the year and more out of shape than he was early in the season which is tough to see.
On a team thriving on hard effort on defense when rotating he can be consistently a weak link. Hearing him talk, he has no issues with his weight and also struggled to even find things he had as goals for getting better as a player. I understand if it's weird to talk about this stuff for him and I don't mean to be a jerk about it but regardless I just don't think he has potential to get better.
He doesn't fit how the team plays. He hasn't proven anything yet, but just looking at what Yabusele could be (potential off the dribble, legit shooter, can run the floor) it stands out what Sully can't do, even for a physical player you want around. I doubt Yabusele is ever that rebounder and who knows if he does anything at all in the NBA yet, but Sully just does not get up and down and rotate like this team needs to. Olynyk is a guy that was seen as weak on defense but last year he really bought into all that and gave a great effort to be able to do those things for the team. Sully hasn't. He's certainly not good enough to change your system for.