That's because most (but not all) cultures today are patriarchies where the presumed inferiority and otherness of women is used to justify differences in rights and opportunities.
Meanwhile, in a lot of mobile hunter-gatherer bands, gender roles may exist, but nobody pays all that much attention to them because they have a culture that values personal autonomy and that largely hates for others to tell them what to do. As long as the person is contributing to the group, nobody worries much about how that plays out. That seems like a lot more stable and functional way to run a culture to me.
Why do you want to live in a world filled with artificial fences? Particularly when trying to force people to comply with them is often quite demonstrably harmful? Why is it so difficult to just live and let live? Seems pretty crazy to me. What possible "stability" can come from forcing people to be other than they naturally are? And what about the instability that comes from oppressing people for refusing to comply? It drives bullying and other forms of interpersonal violence, as well as suicide.
In addition, this outlook of yours is also driving a worldwide movement of women who do not want to get married, have children, or even have relationships with men because they are sick of the oppressive nature of how these things manifest in patriarchies.
“Marriage has mostly not been a great situation for women historically and across the world, and they’re trying to find alternative solutions. As new opportunities open up for women to be full people without it, they’re opting for that,” Hannaford said."
"For Youngmi and many others who subscribe to its basic premises, 4B, or “practicing bihon,” is the only path by which a Korean woman today can live autonomously. In their view, Korean men are essentially beyond redemption, and Korean culture, on the whole, is hopelessly patriarchal — often downright misogynistic. A 2016 survey by the Ministry of Gender Equality and Family found the incidence of intimate-partner violence at 41.5 percent, significantly higher than the global average of 30 percent."
