The Denton report explains a lot. And after the ground was laid, a huge amount of intimidation and emotional blackmail. A lot of people felt that if death and rape threats and genocide accusations were being made then even though that's wrong, it must mean JKR had said something truly evil even if nobody could say what it was, which is of course one reason for doing it. Naturally, women who made such threats to men would never get such sympathy but everyone knows who the women are.
I think a lot of people assumed it was more complicated than it was. The tide is turning because it's becoming clear that yes, they really did mean that men are actual women if they say they are and should get access to changing rooms, sports and so on on that basis. It really is that insane. There's no missing nuance.
Everyone knows men aren't women and by this point it's hard to see any justification for the insanity beyond thinking that women do indeed exist to serve and facilitate men to any degree even if everyone denies it. Even here, as always, we got the "but my lovely trans friends" stuff as if lovely female friends, or just women in general, don't matter now that a man you like wants to get his knob into the ladies'. Fuck's sake.