the truth is, we don’t know [what makes men better at sports compared to women]. but we do know now, finally, after all these years, that it isn’t as simple as natural testosterone. that is not the reason. there are elite world championship level men with natural testosterone below the women’s average, and they’re competing at no disadvantage to men with 100 times as much testosterone.  so there are certainly, maybe, some biological reasons for men, on average, being bigger, stronger, faster than women, but we do know that there are also social reasons.
no evidence trans girls perform better in sports than cisgender girls, says doctor