The church needs to help youth workers gain more education, experience, and exposure to people who've been in this profession a while. I'd say more and more are. But most aren't. I'd say no, but it's slowly getting better. Billy pointed out that churches aren't looking for theological depth these days, but I think many churches are.
Perfect practice makes perfect.
They're not taught anything. That needs to stop. You look at all the other fields that demand practitioners to be licensed, and most of those fields incorporate some sort of internship or mentoring program to the licensing process. School teachers have to earn so many annual credits in order to maintain their licenses. With the new legal issues, especially having to do with counseling, youth ministry licenses may eventually be the law.