and haven't the Nordic countries (who supposedly lead the world in women's rights) been using unisex changing rooms/toilets for years now?
No. I live in Sweden. Changing rooms are open plan here (which I hate) but are all single sex. I’ve never seen a mixed sex change anywhere.
Everything is open plan - changing and showers and like most countries you have to shower naked before using the pool.
It’s a myth that Nordic/Scandinavian societies are all mixed sex everything.