Based on just observing him through the process, it seems like there's a combination of things that might keep younger people away from being an ATC. One might be the unfortunate politicization of government jobs at large, and especially how people like ATC's get affected during those pesky "government shutdowns". There's also, I think, the fact that being an ATC is more or less an "invisible job" to many people and especially college educated people. Also, the job itself can be stressful (but nothing like the horror story myths I've read about, apparently) and the exams to get in whittle down the herd pretty dramatically it sounds like.