You raise an excellent point.
But to me tolerance doesn't mean pretending we're all the same, it means accepting that we're different and being okay with that.
Boys and girls ARE different. I don't think it's all cultural.
I suspect that is true....though, since we have no examples of children raised without the very powerful enculturation that begins from the instant of birth, ( I'm dead serious....adults relate VERY differently to boys and girls immediately) I don't think we know as much as we think we do, especially given brain plasticity.
I just think kids ought to be given as many choices about how they want to be and what interests they wish to pursue with as little pressure to be a particular way as we can manage.
Thats hard though, both because so much of what we do is not consciously apparent to us, and because there are lots of people out there who are ready to froth at the mouth, especially, in modern western culture right now, I think, about boys who don't observe rigid gender roles.
I think many of we western women are living with less gender role pressure, by and large (excluding those living in the thrall of various fundamentalist religions and such) than has ever been the case in history....though stuff like pressure to be skinny and all that kind of thing is still very strong. Were a pretty small percentage of women though.