AntiTrumpAlliance

in most sports, women physically can't compete with men.

I don't know...The gulf between the best male athlete and the best female athlete is so tiny compared to the gulf between the best male athlete and the worst male athlete, though.

Like...the women's world record holder in the marathon set her record with a 2:09:56 in the Chicago Marathon in 2024. She would've come in 18th overall in last year's Chicago Marathon. That's not even 10 minutes behind the men's world record holder, who set a 2:00:35 in the same race the previous year. Over the course of a two-hour race, that's something like an 8% advantage that men hang on to--and that advantage has been cut in half over the last half-century.

Conversely, while of course it's really hard to define the "world's worst" male runner, a speedwalk marathon takes about 4 hours; so if you're running at all, you're basically guaranteed to be half as fast as the best women.

All of which means, a "failed" male athlete stands no chance against a woman. If you're good enough that running against women might improve your chances of a win, you're already an elite athlete; and since you're willing to lie anyway if you're considering transitioning just to win, then taking steroids or something and hoping you don't get caught is way more likely to push you over the edge.

EDIT:

there needs to be some sort of regulation

Maybe, but I think individual leagues and sporting groups should handle that if and when it becomes a problem.