I think I kinda get what the OP is saying. It immediately made me think of a quote from Narnia where something to the effect that Susan's rushing as fast as she can to the silliest time in her life and is going to try and stay there as long as she can. Perhaps because of this quote, I spent most of my teenage years reading books and playing with LEGOs instead.
As for "adolescent," I've also heard that defined as the period when one isn't reliant on adults, but also doesn't have little ones to care for...in which case, yes, "adolescence" is going on longer now that it was in the past.
But...I love YA not because I want to be young again (high school? Ugh, please save me!) but because there are some really great, tight stories being told here of tremendous character growth (coming-of-age). I think the desire to change, to grow, to be a better person is eternal, and YA often has this in spades. I can remember that experience -- deciding who I wanted to be -- and those kinds of stories still resonate strongly with me and make me think about who I'm becoming still.
Also, as noted, the explosions are great.