Yes and no. I think the Bulls aren't too young in general, they're just too young in key places. The most obvious one is they don't have any big guys that know how to play defense. It's pretty much exactly the situation we had with Curry and Chandler before we traded for AD. We needed someone to come in glue those guys together.
I think your expectations are way too high. How many playoff teams can you think of that played a 20 year-old rookie PG 35+ minutes a night? Magic is the only one that comes to mind, and he had Kareem.