I often ride in on the coat-tails of the wonderfully well-informed Keeptoiletssafe in my 'Keeptoiletssimple' persona😁
Here I go again, picking up on that final point, that toilet provision has always been driven by need, not preference or validation or whatever the trans lobby has made it.
Accessible toilets were campaigned for because some people needed the adaptations in order to use the toilet, they physically could not use a standard toilet - it's not that they simply preferred accessible toilets.
Do transwomen need to use the women's toilet? Are they physically unable to use the toilet designated for their sex, and need their own fourth spaces?
The EHRC guidance is reported [I'm quoting from BBC reporting] as saying
leaving a trans person without access to any services or facilities would be unlikely to be proportionate.
That seems to mean 'every venue with standard toilet provision of women's, men's and accessible has to go to the expense of making special provision for transpeople - despite the fact that they already have access to facilities that they are perfectly capable of using, but choose not to'.
I think what is disproportionate is requiring venues to incur so much disruption and expense to cater for a tiny percentage of the population, who can use the men's/women's, but choose not to.
They have not been left 'without access to any services or facilities', they have decided for their own reasons to refuse to use the available services or facilities.
As KTS says, 'It absolutely unprecedented' that expensive, disruptive demands from a tiny minority on the basis of preference not need have been allowed to influence building design, and become such a 'toxic culture war' issue.