Cis people STFU about things you don't understand challenge, difficulty: impossible.
It is NEVER just about sports. If you concede the sports issue, the fascists have a lever to attack all trans rights. Against all available evidence and against all reason, you have conceded the Republican talking point that a single-digit number of trans women that perform poorly to ok-ish in competition with cis women are a "fairness and safety issue". From that, it directly follows that you have conceded the Republican talking points that trans women should actually be treated as men, that we pose the same threat that men do and that differences between sexes that are either purely imaginary or highly mutable are essential, unchangeable characteristics and that "men" in this bio-essentialist, anti-science worldview are inherently superior.
If you buy into their "no men in women's sports" framing, you swallow the fascist bait hook, line and sinker. You have already agreed to their ideology on gender, you have already proven that you will never have the guts to oppose anything of it, as if letting them take Roe v Wade from the people would not have already proven it.