She does also have some concerns about trans women in women-only spaces, but depending on which polls you read, either a slim majority or large plurality of people agree with her concerns.
As for the term "people who menstruate," I could see how that could be true. I could also see a term that's designed to specify a subset of women (pre-menopausal cis women who menstruate) as well as a subset of trans men. It is not being used as a general replacement for "women"; it is specifying the relevant people more precisely than the word "women" would. Isn't that specificity and accuracy what we want to see?
[1] "I know transition will be a solution for some gender dysphoric people, although I’m also aware through extensive research that studies have consistently shown that between 60-90% of gender dysphoric teens will grow out of their dysphoria."
[2] ", I do not want to make natal girls and women less safe. When you throw open the doors of bathrooms and changing rooms to any man who believes or feels he’s a woman – and, as I’ve said, gender confirmation certificates may now be granted without any need for surgery or hormones – then you open the door to any and all men who wish to come inside."
[3] "It would be so much easier to tweet the approved hashtags – because of course trans rights are human rights and of course trans lives matter – scoop up the woke cookies and bask in a virtue-signalling afterglow."
I think it's about 50/50. The one good, recent poll I found on the issue seems to suggest that (I mentioned it at more length in the other subthread here). So I definitely don't think that there's an overwhelming consensus, but I do think that it's a pretty standard opinion.
As for the "material difference" thing, sure. I think almost everyone would agree with that. My problem is that I believe Rowling is using it as a dogwhistle to argue that (most) trans women are not meaningfully women.
Look, there are not a lot of great polls about people's opinion on whether sex and gender are different. PRRI has a poll on general support for trans people (https://www.prri.org/research/americas-growing-support-for-t...), which suggests that 62% of Americans support letting trans people serve in the military and a plurality oppose bathroom bills. It also shows that a majority of Americans believe that there are only two genders, but only 43% of Americans believe that "strongly," and of course you could believe that sex and gender are different while also believing in only two genders. I don't see clear proof one way or another, but this poll suggests that probably about half of Americans believe that gender can differ from sex. (I'll admit that for non-Americans, it's probably much lower.)