I am not going to flame you, but I am going to disagree with you and here's something that I think you need to remember. Okay, gender affirming treatment does not allow a transwoman to grow a uterus, ovaries and the like, that much is true, and yes, cisgender women have had to fight against men trivializing the pain of menstruation, and they have had to fight for their rights, and, thanks to that arsehole who has wrongly claimed that he won all states, but is facing multiple charges, those rights have been taken away because of someone he appointed to the Supreme Court. But denying transwomen access to at least some women's spaces is akin to saying to people who want to take American citizenship being told that they can become citizens, but they can't vote!
There is a false equivalence argument by saying that cisgender women don't want access to transgender spaces, but transwomen want access to women's spaces. Transwomen want to be accepted as women by women, and to have at least some of the same rights as women. Consider this for a minute. I know a woman who is a feminist, who wanted to play soccer at school, but her school said, "No, only boys can play soccer." So, she turned up to school the next day in shorts.
I say, if a transwoman wants to go to a health center and be seen by a female doctor, that's their right and that should be respected.
To take some of what you say, however, I give the example of Father Wilhelm Kleinsorge (aka Makoto Takakura), a German-Jesuit monk in Hiroshima at the time of the atomic bombing. He became a Japanese citizen later on, and he said that when a foreigner hears the term "Tennoo-Heika" (His Majesty, The Emperor) it doesn't have the same feeling as it does for a Japanese. Okay, if Father Kleinsorge had been born in Japan to German parents, attended school in Japan, where he may have been the only foreigner, he may have felt like an outsider, but he might have been accepted by Japanese children, too. Father Kleinsorge had been in the war in Japan, and as John Hersey said, "The Japanese wartime diet had not sustained him." And he survived the atomic bombing, and in the three months between Germany's surrender and the bombing, attitudes towards him changed. (With Nazi Germany being a fellow Axis Power, Germans were viewed differently by the Japanese). He wasn't educated in Japan; he fell in love with his adopted country and took up citizenship.
There are things that a transwoman will never experience, such as menstruation, but there's more to being a woman than that. A misconception that some feminists have, however, is that transwomen want to transition to be able to dominate women's spaces, but in most cases, that's not true. A common example I can think of is Christmas. Islamophobes, like the arsehole who was voted out in 2020, claim that Muslims want to wage a war on Christmas, but most Muslims are actually accepting of Christmas and the genuine people will wish their Christian friends Merry Christmas and in turn, they're wished Ramadan Mubarak. But if you went to Australia for Christmas, you'll find okay, some people, like me, prefer a hot meal on Christmas Day, but as Christmas is in summertime in Australia, some people opt for seafood and salad, and some people will have ham and turkey or chicken and salad. Some women might find it nice if they can think of transwomen like Christmas dinner at my place. My folks have seafood and salad, but I have turkey or chicken and hot vegetables. Both are okay.