[crooked-v]

Sure, but consider the economic factors that go into it. How many extended families would be perfectly happy to live together, but are unable to even consider it in the first place because of what the costs for that sort of multigenerational housing would look like?

[lotsofpulp]

I would guess very few. The main problem with extended families is politics, not house size (which are multiples bigger than they used to be in the US).

It is hard enough to run a household with two chiefs, but add more and you either need everyone to accept a hierarchy or split into different houses. Which is why it is almost only ever seen in places where individuals lack earning power.