There are almost no archeological records for social dynamics, so they usually get ignored, or you're forced to base theories on some exercises of imagination. If you were to discover in 1000 years a smartphone without data on it, I doubt you could infer modern social media without some guesswork. You'd get photos, calls, navigation from it having GPS, but not endless hours scrolling feeds.

For this matter, what's the point in having a huge village? I can only see protection against warfare and forcing fairness in social interactions and on the matchmaking market. Other things seem to get worse, since increased density makes extracting food from your environment harder.

Adult humans have three basic goals: food, shelter, reproduction. They spend most of their energy on these, and any explanation of a society that ignores one of these has to be incomplete. Maybe the fact that we've moved one of these from the social plane onto the virtual makes that harder to see. I've been off the dating apps for some years by the way. :)

Isn't trade more efficient in larger villages, too? Like economics in general

Trading seems a good explanation, yes. A trading expedition is a big deal, you probably want cram a ship-ton of resources together and exchange all your obsidian for salt, or grain for copper, or whatever, in one go. You don't want to mess around making massive journeys between hundreds of little villages. You want a large, famous, easily-spotted trading destination that has all the goods ready in a big convenient pile.

Most of these sites have astronomical/calendrical orientation. I would say the definition of trade has to include knowledge and techniques. I can imagine a culture developing a steady state around the seemingly consistent movement of celestial objects and slowly losing it’s cultural center has things shifted.

I find interesting that astrology is based on the rising of the sun in position of the planets which is distinct from a lunar calendar.

What sort of cultural shift would that change create?

Given how basic their lifestyle was, I'd say you hit marginal returns at tens of individuals. Like I said in another comment, a stronger reason would be required for people to want this scale, and I can only see warfare/peacekeeping and matchmaking as reasons.

> Given how basic their lifestyle was, I'd say you hit marginal returns at tens of individuals.

You might have a circular argument there.

>For this matter, what's the point in having a huge village? I can only see protection against warfare and forcing fairness in social interactions and on the matchmaking market.

Division of labour/economies of scale are fundamental to human quality of life improvements. Even without much technology/industry, there's still a lot to gain from division of labour.

This was a very egalitarian society, with basic needs. All the benefits from division of labour and trade you already get when your society has a few hundred individuals, and it doesn't give you any incentive to grow as large as these mega-sites were.

when tinder becomes tinder