I think he's improved. He's gotten more efficient around the rim. Added that floater. FTs are no longer a liability for him. Found out how to get his shot off against bigger defenders. Learned how to use his quick hands to knock the ball away from opponents backing him down.
He's regressed in rebounding, but that may, or may not, be due to his knees. We'll find out over the next few years regardless of where he ends up.
But, at the end of the day, he's just two short to defend competent post players and offers no rim deterrent as a help defender. A lesser team might be able to live with that, but not a le contender.