On a post about Great Britains sex-based spaces laws that was painted as trans people being “banned” from public restrooms, I pointed out that they are not banned, they just have to use the ones that are for their sex.

Nothing incorrect there. 100% factually correct. Sex and gender are constantly spoken about as being separate things now, since sex is not changeable (despite what the person who replied thinks)
I was then permanently banned for “transphobia”:

Do they even understand what a phobia is?

Sex is a contruct that relates to many things. When people talk about changing sex they refer to changing the external genitals or even just the biological changes that happen when taking HRT. Chromosomes laregly do not matter in this equation and a surprising amount of people have arrangements which don’t fit typical expectations, yet most of these people go their whole lives not even knowing.