When it comes to toilet provision, I find myself guided by the three Ps [Ps -see what I did there
]:
proportionality, practicality and pragmatism.
I can't see any justification or rationale for widespread provision of special toilet provision for such a tiny proportion of the population - the figures are not clear but approx 0.5%. Women, men and disabled men and women are large groups in society, adding up to 100% of the population, and there are clear and well-established reasons for providing separate facilities for them. In the case of disabled people, it is because of need, not comfort or preference, that they require adapted facilities.
It's not practical for existing public buildings to go to the expense and disruption of installing fourth gender-neutral spaces as well as the women's, men's and disabled spaces already in place.
There is nothing that physically prevents a trans person from using the toilets designated for people of their biological sex. Words like 'discomfort' 'preference' 'wishes' do not describe an inability to use the designated single-sex toilets.
Many transpeople [increasingly, I think?] acknowledge that it's not possible for humans to change sex, so they say they have changed their gender presentation, not their biological sex.
In which case, as single sex toilets are designated by biological sex, not gender, they have no reasonable argument for not using the toilets designated for people of the sex they acknowledge they belong to.
In short, when I read these elaborately-argued demands for universal, additional, elective, special provision [and you can add 'expensive' and 'disruptive' to that list] for 0.5% of the population who would like it but don't actually need it, I just can't see any rationale or justification for it.
I feel I should be speaking that last paragraph to a hushed, expectant courtroom while peering over half-spectacles 😁