In every society there are weirdos. You may think of it as an axiom. Weirdos come in all shapes and sizes. These days, sexuality is the preserve of weirdos who go to extravagant lengths to deny their genetic and biological makeup and turn themselves into something else (usually the opposite sex).
The chattering classes and the Commentariat have taken to lionising such weirdos. They are the true heroes and heroines of our age. In order to stand with them it is demanded of society (that is, you) that it ascribe every kind of civil, freedom, and human rights to such people. If a male becomes a trans-female it is incumbent upon SS Society and all who sail in her to accord the "trans-her" the rights of females, including access to women's changing rooms and toilets.
The next iteration follows. Weirdness is catching. Up pops a fellow who makes no attempt at all to resist or deny his genetic makeup. Instead this weirdo says, "OK, I am male on the inside and male on the outside, but I don't feel male. I think of myself as female. I identify as female." Sure, says the captain of SS Society, no problem. So now the guy who is trans-gendered in his mind's eye only is accorded access to female toileting and changing facilities. And so the weirdo and weirdness rolls.