The answer in both cases is 'cultural norms and expectations'. Something that I don't think rapists would give much of a shit about. If a man is willing to break laws to assault someone, a cultural norm would seem to be pretty low on their list of concerns.

Over here in the UK, during the noughties gender neutral bathrooms were popping up in offices everywhere. They were seen as a cool thing that good employers did. It wasn't anything to do with non-cis people demanding it, it just happened organically. It was a fairly brief trend and died out after the financial crash as costs were cut but people of all genders thought they were fine. It seemed a rare moment of sanity to me. We all piss and shit the same way so a loo has always seemed (to me) a very weird place to be designated as a woman only space, or a man only space come to that.

According to the latest census data the trans population of the UK is about 0.5% of the 16+ population with 0.1% identifying as trans men and 0.1% identifying as trans women. Thats about 45,000 people in each group, across the whole of the UK.

The UK has lost its collective shit when it's making decisions that effectively punish trans people based on such an incredibly low number of people, especially when there's literally zero indication that trans women are potential rapists or are in anyway going to negatively affect women's rights. More than half the country are cis-women/girls. How on Earth does anyone imagine 45,000 people are a threat to to 30million+? The trans women I know just want to live their lives without being made to feel like shit.