Yes you are right, my language was really clumsy here. it was late at night and I was starting to ramble 😅.
I've tried to clarify what I've meant more precisely since.
I think the problem is that people understand 'gender'/ social gender categories/ roles as being reducible in a simple way to 'stereotypes'.
The reasoning then becomes: if someone experiences a gender that does not align with their sex, that must be because they have internalised mistaken stereotypes about what it means to be male or female. From that perspective, the solution is to challenge those stereotypes and change society so they no longer exist.
I wanted to acknowledge that there is a certain logic to the idea that, if we lived in a world without socially meaningful categories of male and female, then the experience of being in the "wrong" one might also disappear.
The difficulty is that this strikes me as utopian. We can and should challenge harmful stereotypes and reduce the extent to which people are constrained by gendered expectations. But I don't think we can eliminate the social significance of the categories themselves. They are not only collections of stereotypes; they are rooted in real biological differences that have social consequences. We can reject the idea that women should do the cooking, for example, but it seems much harder to imagine a society in which being male or female carries no social meaning whatsoever.
Indeed, if anything, current developments appear to be moving in the opposite direction. The EHRC guidance, for example, places renewed emphasis on recognising sex-based categories and organising some aspects of society around them.
Categories of male and female therefore remain socially meaningful. So too does the experience, for a minority of people, of profound distress at being somehow in the 'wrong' one - physically and socially. That is the phenomenon referred to as gender dysphoria.