Realistically 3 spaces will mean they slap a gender neutral sign on the disabled
Every disabled loo I've ever seen is "gender neutral", ie mixed sex. My husband was disabled, I went ti multiple disabled loos with him, including airports, restaurants, etc. Never seen a sign other than the disabled sign on it -- they don't need a "gender neutral" sign.
I dont view religion, which historically has been one of the biggest surpresssers of women as a good argument. Not in a predominantly atheist country.
So, because you are an atheist, you believe that Jewish, Hindu and Moslem should not have access to single-sex toilets. Lovely.
I also doubt that Britain is a predominantly atheist country. Even if the traditionally majority religion, Christianity, has lost its appeal for many, even if people don't go to church or call themselves Christian any more, if you dig deeper you'll find that many still pray when it comes to the crunch. Add to those millions of Moslems, Hindus, Sikhs and Jews, you can't really speak of a "majority atheist" society. And even if you could -- this has nothing to do with most women wanting single sex loos.