OK @PlanetJanette.
If I had unlimited time and money, this is what I would do.
I would have two groups bring legal action against the UK government, claiming that the current system is in breach of their rights under the ECHR and the Equality Act.
One group would be women from religious minorities, who argue that allowing members of the opposite sex into women's single sex spaces is a breach of their right to practise their religion peacefully and constitutes indirect discrimination against them because it has the effect of forcing them to self exclude from public places.
The other group would be non binary people, who argue that they have the human right to recognition of their gender identity, and that the fact that there are no toilets, other single gender spaces or sporting categories for non binary people is a breach of those rights.
Just as those were working their way through the court system we would introduce two more. One group of female survivors of male sexual violence who would argue that being forced to share single sex spaces with the bepenised sex amounts to degrading and inhumane treatment and is therefore a breach of their rights under the ECHR. And another group of catgender people, seeking the same provisions as the non binary people.
You just keep overwhelming the system until the inevitable outcome is the following:
- single sex spaces are guaranteed in accordance with the Equality Act
- service providers are required to provide single sex spaces and services but may also provide unisex/non binary/catgender spaces and services should they wish to do so
- the GRA has no effect other than allowing people to be legally recognised as whatever "gender" - NOT SEX - they like
- ID documents end up having a compulsory biological sex marker and an optional gender identity marker
- "TERFs" troll the new system by getting gender recognition certificates which legally recognise them as icecreamgender, jedigender or donthaveapenisgender, which are of course every bit as valid as "non binary"
Any flack from the "international human rights community" is met with a, "Yes, we know, but the thing is, and I know this is a bit awkward, but people who aren't trans also have human rights too, and this is the only way we can see of balancing everyone's rights."