Sometimes one thinks of the bathroom thing as "two separate spaces," but that isn't really true to their purpose. In the beginning, all public facilities were unisex, but women campaigned for and received the right to their own bathrooms to protect them from men. Since all women immediately switched to using women's facilities, the old bathrooms became the de-facto men's bathrooms, but that's not how it worked originally and that's not the best way to understand them. Anyway, trans men aren't a threat to natal men, so I'm all for it. It doesn't change the calculus of danger for anyone except the person making the choice.