https://www.thehelenjoyce.com/p/why-gender-medicine-isnt-science
“Actually that’s not quite right, because there isn’t any requirement to perform your gender, just to state it. Nothing further than the statement is required of the person making it: it’s other people who have to do the work by believing that statement — that is, by “affirming” that gender. The expression “gender self-identification” is a misnomer — it’s not something you have to do, beyond proclamation, it’s a demand that other people affirm you as being the gender you state yourself to be. Opening the door marked F or M is a way of declaring your gender identity.
There’s no place for other people’s judgment, indeed no role at all for other people except as supporting actors or appreciative audience. No room for them to say they don’t fancy joining in the performance, or to be a critic and say it’s not a very good performance. They’re not allowed to say: “OK, you say you’re a woman, that you’re living as a woman or have a female gender identity, but you don’t seem very female to me.”