I wish people like this would get into the habit of just saying "trans women are women, they are women with a medical condition but they are women". There's nothing wrong with acknowledging the differences between cis women and trans women so long as you acknowledge the baseline -- they are women. The same goes for trans men and cis men, but they're consistently left out of discussion because this is and always has been about patriarchy. Trans men aren't as offensive because they're claiming patriarchal power whereas trans women are perceived as threatening to patriarchy as they're perceived as people giving up patriarchal power.