you keep bringing up age which is why i said what i said. when you say adults you are talking age. like i said before it's no different from a company having on their app "must have 2-3 years of experience". this is the elite of the elite so there should be some kind of requirement to get in. being good in high school and making 18 isn't enough. you might be adult age at 18 but you are still and immature kid at the end of the day. I need to see you against other potential pros and see what you can do.
It's completely different. As I tried to explain before, the Boston Celtics could have a policy of "we don't draft anyone who hasn't played at least two years of college ball because we think scouting high school kids is too difficult" and that would raise ZERO antitrust issues. But for all the teams in the NBA to get together and agree that none of them will draft kids who haven't played two years of college ball? That's the antitrust issue.
So, to try to give you an analogy outside the sports world... If Apple said "our company policy is to not hire any programmers who don't have 3 years of programming experience" that's not an antitrust violation. But if all the CEOs of every major silicon valley company got together and agreed that they would all adopt the same policy? That's almost certainly an antitrust violation.