trisher, you are right that unisex loos may be the answer, as are unisex swimming pool changing rooms (I mentioned this on the other thread - at our pool everyone must wear appropriate swimwear in the showers, for example), but in a single sex loo, at a quiet time, I think most of us would feel intimidated by the presence of a person, who is obviously physically a man, just hanging about.
Amma54, I understand from DD that the acronym TERF has been hijacked by those who are against simple self-IDing and now says Trying to Explain Reality to F***wits, and good for them, I say!