Differences between men and women are not just physical

NB: I already addressed the overal issues with "transgender" male atheletes competing as women in this more extensive article here:

https://www.minds.com/SMetzeler/blog/transgenders-in-sports-1219909602241261568

This is a shortened version that only addresses the mental issues:

Mental differences between men and women are significant

While people pay a lot of attention to the physical aspect of men - including "trans women" - competing against women, this is only a part of the issue.

There are significant mental differences between men and women, including a much stronger drive to compete and win.

e.g. only 1 woman managed to become one of the top 10 best chess players and that is not related to the number of participants, as often claimed - here is a detailed study on the issue:

Explaining male predominance in chess
https://en.chessbase.com/post/explaining-male-predominance-in-chess

Another study found that men perform much better at scrabble, although 85% of all scrabble players are women:

Gender differences in SCRABBLE performance and associated engagement in purposeful practice activities 
https://link.springer.com/article/10.1007/s00426-017-0905-3

The author of the study comes to the ridiculous conclusion that "men win because they make much greater efforts to gain skills that are essentially useless" and that women would be able to win if they were as driven as men. Which misses the entire point of the male-female difference! The fact that men do try so hard to win is specifically a trait specific to men, which very few women share.

Men are more frequently on the autism spectrum, which implies greater social difficulties, but greater success in activities that require extreme focus, such as chess and scrabble - which includes STEM professions.

The same ability to focus will also give them an advantage in physical sports.

Need more evidence?

There is no reason why girls should do worse in e-sports than men, right? It's not "physical". Yet the only all-girl team in e-sports lost miserably in all competitions, although they received extensive financial and moral support and were heavily promoted:

So it is fundamentally unfair to have men - including those who underwent hormonal treatments and operations - compete against women.

There are good reasons to have competitions that are specifically for women only that go beyond the physical aspects.