Let's hold the phone a little here. Rob is averaging 10/9/2 with 3 blocks and 1 steal a game, shooting 69% from the field and 67% from the FT line. His fouls per minute are incredibly low and his turnover rate has dropped significantly. His defensive rebounding has suffered a massive drop, but his rim protection is still there - 3rd in BPG (Horford is 1st) isn't bad. A lack of rim protection is not our issue IMO.
His role has also changed. He's getting much less of the ball, which under-utilises his passing ability. He's playing in two-big lineups, which I don't think helps either. He's also gained weight to battle against the bigs, which makes sense given that was a glaring weakness of his and we don't have anyone else who can (because Kanter doesn't get minutes).
He's not been as dynamic as he was, but he's playing 30+ minutes of good basketball.