the evidence for being "born in the wrong body" is largely unconvincing
I had an interesting conversation with an internationally fairly famous philosopher (as far as any philosopher is famous
) about this belief - her view was that it is a very masculine-socialised world view, deriving from Descartes, whose separation of the mind from the body, and whose rational (but reductive) proof of existence was, "I think, therefore I am" was a peculiarly gendered & classed view.
To be able to separate one's mind/thinking from one's body & bodily functions, is a privileged position: a position that suggests one is not a manual labourer, for example, in a position where the labour of one's body is at the centre of continued existence (food, shelter).
Or it's a position which suggests that one is not subject to bodily conditions which can dominate one's consciousness (regular/cyclical uterine pain from ovulation and menstruation, or swings in mood caused by hormonal cycles), or it's a position which suggests that one has not been through experiences where - as much as one is a thinking being - one's body takes over - pregnancy and childbirth, for example.
Women have always been necessarily aware of our bodies; we rarely have the luxury of pretending we are only minds/consciousnesses. I'm privileged to spend most of my time thinking, but I am still reminded daily that I live in, and only exist in, my sexed female body.
I suspect it's always been easier for men, and particularly privileged men, to behave as though they are minds only.
This philosopher I was talking to about this said to me: "Oh as far as I'm concerned, it's just another version of the problem of the Western mind/body split, and all the trouble that's got us into over the centuries."
She published something on this in the 1980s - feminist concerns about transgender /transsexualism are not new.