Common sense covers it, why do some people feel the need to make laws just for the sake of it.
Some people might say "I am a woman who goes to the local pool with my 8 year old daughter and 14 year old daughter. In the communal women's changing rooms and showers, I don't wish them to meet a naked person soaping their cock and balls."
Does common sense say she is entitled to be in a single-sex area, or does it say that the person is entitled to be in it?
presumably you are aware that there are people who hold each of the conflicting opinions?