I myself have wondered this. When I first started following the Elite sereis when I was younger names like Clunn, Grigsby and Shultz were studs. However, all it takes is a look at the Elite AOY standings and scroll to the bottom and many of those guys are there. As a former Highschool angler myself I wonder if programs for youth, hs and college along with electronics have contributed to it.
My second theory is a little more controversial. With all do respect to the guys mentioned before, I wonder if competitive drive is something. Competing in high school state, regional and national tournaments I have been exposed to solid competition and they have instilled in us a drive and path to make it as a professional someday if we so choose. As well, the education side has been incredible, each of the high school tourneys I was in was a learning experience in of itself being able to fish across the Midwest... as well as educational opportunities to learn more about the biology of fish and patterns along with how to be more efficient with electronics.
I do not mean to sound like a punk kid by this, I am just bringing a point to the form that putting young anglers in tourneys like they now offer and giving us the tools to succeed we go into our future tournaments more prepared and confident.