Just to say re unisex provision, yes, it absolutely could happen.
We're talking about government funded lobby groups, extremely wealthy ones, extremely wealthy donors, direct ear of parliament and many influential groups, the ability to get issues straight into parliament - which is why many GC women are here, because there's been no consideration of women's needs and issues and rights in doing so.
But the point is, if that lobby and all it's might wanted additional unisex facilities, they could very easily campaign for this and get it. It took the disabled lobby decades, and it did eventually happen. There was no money for disabled/accessible loos, no space, huge resistance, but it went into law and funding grants were made available and new build requirements were set and counties supported and enforced that it was going to happen regardless of complaints, and it did.
The lobby in question has way more power, way more money, way more government influence and enthusiasm, and women's groups would get right behind this too. If it was wanted, it would happen and it would take a year or two before major change was visible in most places, and five to just be the fixed norm, as with disabled toilets.
But there is a reason this is not a wanted solution, but male people using female single sex provisions is. That elephant has to be addressed.