When her being "canceled" started people were thinking her book was making a trans person a villain. Which, based on their logic, apparently no trans person could ever be a villain and no individual trans person could just be a shitty person.
There were a couple of big threads on a Reddit community I sometimes browse the other day where they were pointing out threads on r/amitheasshole that featured trans people being assholes
in any capacity whatsoever and claiming that every single one of them was a TERF psyop intended to dehumanize trans people and make everyone hate them. Like, the idea that trans people could even
be assholes or creeps was something so outrageous to them that they didn't believe a single one of the threads was legitimate. It was insane.
And from skimming what JKR wrote a while back, I don't think she ever said explicitly that trans women weren't women. I think she just emphasized on women with uteruses, which is a fair assessment since she personally knows the experiences of being a woman with a uterus.
She said trans-identified men are
male, which is biological fact no matter how much the trans lobby wants us all to believe it's not, and that allowing men to self-ID as women invites any male predator who pleases into women's spaces regardless of whether they're a True And Honest Trans. IOW she supports trans-identified people but also supports there being actual guidelines a person has to pass in order to get their gender legally changed and have access to the opposite sex's spaces in order to prevent predators from taking advantage and doing horrible things. But the trans movement is heavily against any kind of "gatekeeping" and has been pushing self-ID laws (whereby a man would simply have to go and declare "I feel like a woman" to have his gender legally changed, no need for any therapy or "living as a woman" or anything like that) for some time now, so this is "hate speech" and means she wants delicate trans woobies dead.
It used to be that you couldn't get your sex marker on identification legally changed until you'd had genital surgery, which itself required loads of counseling and at least two years of living "as a woman". And when that was the case, it was mostly fine - very few predators are going to put themselves through that much of a time commitment just to access prey or boundary-cross, there were safeguards in place to identify those men and stop them, and there were very few cases of predatory behavior from trans-identified men in women's spaces (because there weren't that many of them, most of them were gay, and they had to be severely dysphoric to get as far as having a legal gender change). But under self-ID laws, there are
no requirements whatsoever. Any man can rock up to the court, declare "I feel like a woman" and his birth certificate and all identification can be changed to "F" and he has free access to any and all women's spaces just like that, no effort required. He doesn't even have to grow out his hair, let alone show evidence of genuine sex dysphoria. It doesn't take a rocket scientist (or even a sociologist) to tell you how that enables and encourages predators.
But really, most of what she talked about was the epidemic of young girls being identified as "trans" and pushed to mutilate their bodies and sterilize themselves before they can even legally buy a pack of cigarettes. The thing is, the trans crowd doesn't care about women and girls (whether they identify as trans or not), so... they don't acknowledge this part at all.
Also, seriously, the vast majority of women are "women with uteruses". You can just say "women". If you want to talk about trans-identified men, you should refer to them that way, or at least as transwomen or whatever. They aren't actual women, and we actual women aren't going about holding our uteruses in our arms like babies or something, which is the imagery that language suggests. What you're saying is that JKR has experience
being a real woman and thus knows and talks about the dangers
real women face.