Society shouldn't 'bend' the rules, but it should evolve when presented with new information. I don't think biological sex will ever be completely thrown out as a concept, but it can grow to be compatible with multiple genders. After all, even though by and large sex is split between male and female, there is a non negligible population of intersex people, who the binary fails to satisfy.
But at the end of the day, all I'm arguing for is the separation of gender and sex. I am fully aware that a lot of our culture and society was built around the idea that these are connected and absolute, and I know that change will be slow and clunky, but, and now this is my opinion again, I think in the long run it will be healthier for everyone.