Obviously this won’t work for all sports, but things like football, track, soccer, it would allow for de-gendered team, even allowing athletes with the skills but not the genetically-endowed physical attributes to have a place to play.
Note: I know very little about sports and being on a sports team, so please point out anything that doesn’t make sense.
I have a lot of experience and I am very LGBTQ+ friendly. I only label as extremists those who push beyond the bounds of, “Everyone has rights, gender is a social construct and you can identify as whatever you want” into denying that male and female are things or claiming that identifying as a woman somehow magically makes you female. The whole, “You can’t question what we believe or you’re a transphobe” is EXACTLY the same as, “You can’t question the actions of the state of Israel or you’re an antisemite.” It’s utter nonsense. Those are both examples of extremism.