Not sure what basketball you watch where 7 footers have the skills in ball handling, passing, and shooting Olynyk has on the floor.
He has a ton of potential because he already has these skills few players his size have even two of. Does he do them at elite levels yet? Maybe not, but I think it's clear to see him getting there very soon.
His rebounding is certainly no worse than average, and as for defense, I think he can be solid. I don't ever see him as a plus defender, but is Dirk? He will have weaknesses in his game. I really like him as a super versatile big on the offensive end.
Not as good as Dirk is a bust? That's the measurement?
As to a Sully comparison, I think Sully would be head of Olynyk right now for me but not by too much because of Olynyk's height and also how valuable bigs with his type of skills are in the NBA right now.