Newborn baby boys and girls have identical brains. It’s only when you add in socialization and eventually, hormones, that you get any differences at all.

This is blank-slatism, an ideology proven false by science.

Are there any differences in the development of boys' and girls' brains?

Electrical measurements reveal differences in boys’ and girls’ brain function from the moment of birth. By three months of age, boys’ and girls’ brains respond differently to the sound of human speech. Because they appear so early in life, such differences are presumably a product of sex-related genes or hormones. We do know that testosterone levels rise in male fetuses as early as seven weeks of gestation, and that testosterone affects the growth and survival of neurons in many parts of the brain. Female sex hormones may also play a role in shaping brain development, but their function is currently not well understood.

This comment is interesting:

It’s one of the most harmful fundamentals of patriarchy — that to be a man you must look and be a certain way and to be a woman you must fit other boxes.

Perhaps you can explain to me why people want to transition, then, if not to fit into these boxes? It seems to me that we were (thankfully) well on our way to simply throwing these things out, and accepting tomboys as tomboys and girly men as girly men, but now everyone’s jacking their kids up with gender hormones to try and squeeze them into those boxes.

Why?

Seems fundamentally counterproductive.

This may be true:

Up until about 6–9 thousand years ago, the foundations of societies across the globe were based, not in warfare and domination, but in largely cooperative and egalitarian societies. They weren’t Utopian, but they did not have some of the traits that some people consider to be inherently masculine as a part of the fabric of everyday life.

…but what won out are societies that emulated the behavior of the ants. And those societies won for game theory reasons. HWFO speaks about that here:

We Are All Apes Behaving Like Ants

And even in those societies you mention, the differences between men and women were clear, and genetic. Early tribes praised women because women were more important to the future of the tribe. One man and ten women can still make ten babies. One woman and ten men can only make one baby. So you send the men to slay the woolly mammoth, so your women don’t get trampled. This is where male disposability comes from, which may in fact be an important root of the modern male suicide problem.