True, but I don’t think chromosomes are really the issue here. If the definition of a trans woman was somebody who has had gender reassignment surgery, I think I’d make the case for them to be treated as women in all cases except sport.

Maybe I’m missing something here, but I don’t see the argument for excluding trans women from women’s spaces if they’ve been diagnosed with gender dysphoria, no longer have a penis, and are living “as women.” Their chromosomes don’t seem very important at that point.