Monogamy is one such structure. It seems very tied to the modern idea of the "nuclear family." There are others. Having an extended family all living together is another. Tribes where children are raised communally is another.
Communal living is highly overrated. If you're a young and capable person you'll be shouldered with responsibility and live under the thumb of your elders. Not a dignified existence. I barely tolerate my own parents, I will not tolerate my extended family demanding things from me.
It's highly underrated by young people who don't like the idea of living with their parents. Ultimately, the cost of this is shouldered by day care fees, parental leave, social security checks we cut to old people, and less efficient living spaces; problems which were ok in an era of gdp and population growth, but in the era of stagnation? We'll see.
> Having an extended family all living together is another.
Collectivism has clear benefits but comes at a steep price: the need to establish and enforce group norms. The nuclear family seems like a compromise in this space, a revealed preference.
I mean, I would probably be happy living like an Orca in a matrilineal family group but, then again, I've always gotten along with my Mom. What about the people who haven't? Or who only started to once they moved out? Those people would be faced with living in a disharmonious environment or leaving to a world hostile to individuals.
