It will be enforced in the way it's always been enforced. By people respecting the rights of women to have single sex places. It's why the majority of men dont walk into womens spaces, no one is stopping them physically. They mostly have respect for womens boundaries.
There was the horrific case of the 10 year old girl assaulted by a transwomen in Morrisons toilet. Its also not ok to say apart from prisons, prisons are a key part of this debate. I guess it depends what number of women you think is ok to be assaulted to meet the needs of men. As I have said this debate keeps getting dragged back to toilets, which is the least difficult issue to solve. Single sex and mixed sex. Solved it I am a genius. What is wrong with that solution trisher?
I dont think transwomen are dangerous, I think they are the same level of risk as men. I would be saying the same if someone suggested men with ginger hair used female spaces, I dont think men with ginger hair are dangerous particularly either.
I don't want people to be persecuted strangely enough, I want trans people to be protected from discrimination but I want that for women too. If you provide only mixed sex facilities (and I at least think that is more honest than saying some men can access womens spaces) then you exclude many many women from those spaces. It's also about womens privacy and dignity and the right to consent.