Except they haven't. There are a small handful of examples, that people both greatly exaggerate, and repeat over and over again. Trans people have been allowed to compete for many years prior, and have not overrun women's sports.

Simple math is that even being a small minority, trans people will, occasionally, win things. Even if there are zero competitive advantages to being a transgender woman, some trans women are gonna excel. Finding a handful of examples of trans people being good at sports isn't actually proof of advantage.

200-yard freestyle race at the Ivy League women’s swimming

Is the type of race that can be totally dominated by up and coming Olympic athletes. Regional/institutional races tend to have quite low records until someone top-tier happens, by chance, to participate in them in the course of their career.

women's indoor 1,500 meter long distance running event for ages 50-54.

My sides. A senior event. At that age the only one you're competing against is yourself.

The Canadian Powerlifting Union announced a gender self-identification policy earlier this year that allowed athletes to participate in women’s competitions on the basis of self-declared gender alone.

Yeah that's bullshit there's a reason the rules set by all other organisations involve something along the lines of a minimum of two years on HRT. Noone at all anywhere is claming that the act of identifying as a woman, alone, reduces muscle mass.