Eh, I wouldn't be so sure. Bathroom etiquette (as with all etiquette) is fluid. It has been different in the past and will be different in the future.
You are right that there will always be someone willing to cross a line, but those kinds of people are not likely to be encouraged by unisex bathrooms... just as they are not likely to be deterred by the opposite.
I'm not sure of an example in history of a culture that had unisex toilets and bathroom facilities as its mainstream custom, (but you are free to enlighten me). The separation of the sexes has typically been the default in this regard as far as im aware.
Now when i talk about 'someone crossing a line' that does not necessarily
have to mean your average pervert, it could litterally be anyone at anytime for a number of reasons from an accidental flash to a brazen act of drunken revelry which could easily be flagged as a S3x crime if someone felt the need to make enough of a deal about it, the reverse can also become the case when someone wishes to complain and wave their conservative values in the faces of those in charge. This invites headaches for the business concerned or the local authorities that manage the WC.
Now my arguement is being presented from the perspective that Unisex become the
mainstream (see my op) in all public bathroom facilities in a given country, i have no issue with unisex bathrooms personally and the inclusion of this in nightclubs for example does not phase me because a night club is a place you visit and expect an open liberal atmosphere, but for unisex to become the standard in the highstreet i do not think that this will ever happen outside of some idealised culturally uniform liberal utopia.
I live in the U.K and we are told every day that the U.K is a multicultural society... which means that we are supposed to be a culture of cultures, we have many representative groups who live here ranging from liberal progressive attitudes to more conservative orthodox religious dogmas, the latter of which i know would have a serious issue with public restrooms becoming mainstream unisex and that does not include the people who are just morally and politcally conservative.
Any business or local authority that manage restooms for public use would have to concider the cost and practicality of catering to the publics desire to relieve themselves and freshen up (the basic tenet of a WC) or too pander to social trends related to identity politics. They can have two bathrooms to manage, one male and one female and be done with it or they can have a 3rd unisex bathroom (or just a unisex bathroom) for those who feel the need to virtue signal while they pee... all while adding running costs and increasing the likelihood of headaches to the owner as they take the risk of inevitable gender conflict that this enviroment would invite.
Mainstream Unisex bathrooms... i dont think will ever happen.
