https://www.independent.co.uk/life-style/caitlyn-jenner-trans-girls-sport-teams-b1840887.html
The hard Left is eating itself. If it weren't for the First Amendment, facts would already be illegal. Yes, of course biological women are getting screwed in some sports because they have to compete with trans women. There are things that don't change with hormone therapy which still give people who were born male an advantage in a lot of sports. Young women are losing athletic scholarships to trans women at best and having their skulls cracked open and worse.
This is more complicated than political correctness allows it to be.
But, we're living in a post-fact world wherein Jenner, who was "Stunning and brave! And if you don't say so you're transphobic!" a couple of years ago is now, herself, being labeled as transphobic by those same people because she's not towing the politically correct line.
The position that a year or two of hormone therapy reduce all biological advantages is without merit.
This is the crux of the argument. Those who are on the side of letting males compete with females will cite evidence that males can have their muscle mass reduced, etc to the point where athletic advantage is almost negated.
The devil is the details. "Advantages are almost entirely negated" translates silently to "some advantage always remains."
And that is the end of the discussion. It is inherently unfair to females to allow biological males to compete with them while possessing some of those advantages.
It is preposterous to allow them to compete with all of their God-given physical advantages. For now, at least that is acknowledged. So it comes down to shaving off those advantages. Except you can never shave them all off. You can never fully measure or guarantee this.