Maybe if everyone stopped banging on about how men and women are profoundly different, stopped declaring babies’ sex before they’re even born so they can buy them the socially expected clothing and gifts, stopped unnecessarily dividing up children in primary school into boys’ and girls’ teams, changing rooms etc, then we would see how that changes things. You clearly don’t think it would make much of a difference. I disagree
You're conflating two completely separate things here: sex and gender.
banging on about how men and women are profoundly different
This is sex. Chromosomes, reproductive systems etc. Men and women have different types of bodies.
stopped declaring babies’ sex before they’re even born so they can buy them the socially expected clothing and gifts
This is gender. The 'socially expected' bit gives you a clue here. I agree with you that it would be better if everything wasn't so 'gendered' from birth.
stopped unnecessarily dividing up children in primary school into boys’ and girls’ teams, changing rooms etc
Sex again. Boys and girls have different types of bodies (those chromosomes and reproductive systems again). Even before puberty, the two sexes are not totally equal in terms of sporting ability (although I'll admit here that I'm not sure how great the difference is, so it might not matter too much, particularly for the youngest children).
As for changing rooms, many girls start puberty whilst at primary school. It must be difficult enough for them already if they are one of the first to have their body show changes, without having to expose themselves to the boys as well.
You clearly don’t think it would make much of a difference. I disagree
I'm with you all the way as far as gender is concerned, but it's absurd to pretend that sex differences don't exist.