I mean, a big component of professional ballet involves the use of beta blockers to prevent girls from showing the signs of puberty.

Some of that is on athletic grounds - maturity brings changes to the body that impede the performance of the ballerina. Some of it is purely aesthetics. In fact, until fairly recently, women professional Olympians would avoid puberty to maintain the lean look that judges preferred. Only in the mid-90s/early-00s did we begin to see the power figure skaters and gymnasts who took advantage of the increased mature muscle mass to outperform their younger peers. Someone like Simone Biles would never have moved passed the preliminaries in an 80s-era Olympic competition.

But you could play the same game with male athletes and steroids/HGH/etc. Practically every professional uses some kind of performance enhancing medication of nebulous legality. And the younger you start, the greater the benefits over your career.

I gotta ask, if we're so worried about this, do we need to get rid of professional athletics entirely? Or are we going to accept some degree of young body modification and parental control over their bodies?