I decided to check in on the show this year since it is the final season. I mostly have been fast forwarding and just listening to some snippets of the singing.You are right about the teenagers. A couple of them are pretty decent, but more of them are not doing well at all.
I watched the episode with Kelly Clarkson guest judging because I do like her. I suffered through some bad singing and rambling comments, but I did like Kelly's rapport with the other judges. She seemed to raise JLo's comments a bit.
The music industry has changed so much, that I doubt any of the contestants will do much after the show. I guess if they can get some better gigs from the exposure it will be worth their effort.