I just disagree with this assessment. In my opinion, the young guys are as good as advertised. Gomes is an outstanding role player, and a valuable commodity coming off the bench. Green has tremendous ability on the offensive end of the court, but has yet to develop that same ability defensively. Rajon Rondo has incredible quickness, but is still so raw.
If anything, you missed the biggest reason why this team is in the lottery... coaching. Doc Rivers is the worst coach in the league. He has proven he cannot juggle a rotation of players and continues to fail developing young players on the defensive end of the court.
Coaching was by far the biggest reason the Celtics had an abysmal season this past year.