I am also a trans ally with several trans friends (all MtF), & believe that the change in law regarding toilet access is wrong & humiliating & had not been thought through properly
I certainly don't think you have thought it through, I agree.
Women's single sex spaces are not there to make men - of any gender and at any stage of 'transition' however you see that - feel dignified, or comfortable, or anything else at all. They are not there for men in any way, that is not their purpose.
Are you a believer in inclusion? Diversity? Religious tolerance? Disabled access?
If you let men into women's spaces so they don't feel 'humiliated' you have to bar access for the women who cannot use mixed sex spaces, often because they are women of minority cultures, faiths, disability, trauma, survivors of VAWG. Is it right that those women should have nothing and be denied all public access? Should those women be excluded from women's single sex spaces and facilities so that no men feel humiliated?
Seriously?
And that's already based on that anyone who is worried about men feeling humiliated if they're not allowed into women's spaces has already dismissed the humiliation and basic fundamental needs of all the women in that space or who ever will use that space as secondary to the needs of those men.
There's a term for seeing men as always higher priority than women on a sexed basis. And you cannot argue that you're not doing this: you don't care in the least about all the groups of women affected, only this one group whose defining aspect is being biologically male.
The SCJ thankfully confirmed the law that protects the rights of women (and incidentally of gay people who also need their legal protections on sexed basis to remain protected), against those who will always put men first and see women as so wholly unimportant and unequal. And who would see women and gay legal protections removed where these are inconvenient to men, on the grounds that women and gay people are lesser humans than these men.
The guidance based on the SCJ's confirmation of existing law is that there should be provision for everybody. I'm afraid that does include women and gay people too. Equally to these men. You can provide an additional space that respects someone's choices and feelings about their identity and body that means they do not have to choose between their own sexed space and nothing. Then no one is left without a space.
But if you let men into women's spaces because awww bless, humiliating for them otherwise - what exactly are you going to do with those women who cannot use mixed sex spaces? And who because of the issues and exclusions and discriminations and harms and in some cases serious injury fought through the courts for years and years to say they needed single sex spaces even if men find this emotionally distressing to permit them.
What is your solution to this?
I suspect I know, and it's merely to let women carry on suffering and shut up about it, because they are after all only women.