Again, I don't really see this as any different than the little boys signed up for Little League, or another kids' sports team, as soon as they're big enough to hold a ball. I know people who have 3- and 4-year-olds signed up for soccer teams already. But when it's men/boys participating in sports and getting scholarships for athletic ability rather than academic talent, while some complain about the lack of academic talent, nobody is saying, "I can't believe in this day and age, they still allow boys to be paraded around for their physical attributes/abilities rather than their intelligence." Nobody questions if they are making a choice, or suggests they can't make that choice themselves. They are no less "conditioned" from an early age to prefer sports over some other activity.
By the time someone is into their teens, I think they're fully capable of saying, "Yeah, it was fun playing dress-up as a kid, but I really don't want to do this anymore." If they're not enjoying it, when they hit the rebellious teenage years, they're going to refuse to keep doing what their parents are telling them to do.