Any change in the law would affect everyone, not just trans people. What about women who have facial hair due to polycystic ovary syndrome? What about women who don’t conform to stereotypes of what a woman “should” look like? These stereotypes, by the way, often have racist undertones. They’re stereotypes of what a white “woman” should look like. Lots of women already experience issues from other women when they use the toilets, but a change in the law could see them being excluded from public toilets along with trans people.