That's perfectly clear to me, Madgran. Where does it stop?
Allowing people to identify as they wish is fair enough, but insisting that everyone else buys into that identification is where the problems start. Where there is differential treatment between the sexes it is for a reason, but taking it away removes the protection but the reason it was needed is still there.
Also, asking people (particularly children) to deny the evidence of their eyes and call men 'she', or accept that a drag queen is a woman, or a cat is a child is deeply dangerous. We need to be able to trust our feelings, and to describe what has happened to us in language that makes sense.
Sexual assault and rape are different things. 'He followed me home' is not the same as 'she followed me home'. Girl Guides camping together has a different set of connotations from a mixed sex group sharing a tent. The more the language is colonised the less the real meaning is clear, and none of this is to the advantage of women and girls.