I don't understand your complaint. Trans people can suffer from PCOS.
Let's see what the pinned post on the still operating PCOS sub says:
https://www.reddit.com/r/PCOS/comments/hmlhjc/rpcos_is_an_inclusive_community/
I have no idea how you would prove this is true, but it strikes me as very plausible. There's a pretty common pattern that unfolds whenever one of these dens of bigotry gets banned from the site. usually the mods/members attempt to make copycat subreddits, which are usually swiftly also banned by the admins. When these copycats fail, they attempt to flock over to some smaller, niche subreddit and take it over.
Sounds like when "GenderCritical" got the boot, all the TERFs came flooding out looking for a new home and caused a few kerfuffles, which were dealt with.