This is interesting on a number of fronts
Mostly Cultural bias . Many cultures have loving stable families where having your “own bedroom” is not a factor. Not due to poverty - due to preference
Many Asians live in extended families and I took my wesrern / nuclear family to visit one abroad once. We saw many wonderful things but the thing that stood out for them was the shared communal life . Rooms were assigned to adults of a certain status but not to youngsters. Children could therefore bunk in with “granny and grandad” on the night he promised ghost stories or they could
Bunk in with the other kids and it would be sleepover
Or my kids could be boring and come sleep
With me
The difference is that in a wealthy family where there may be 2 brothers, their wives and kids , grandparents ( as nominal head) and extended cousins who may be at boarding school / job placement for a term and nobody would dream of a hotel
They might be wealthy - but not have enough rooms to accommodate all. So it might make sense to have a girls room, a boys room , or the tots co-sleep with granny whilst mum has the baby
All
Very normal
Also - the beds . They would often be flat and hard ( think Japanese mats rather than air spring mattresses that we have ) and therefore made to whatever size you want - usually the bigger the better if it is a hot country and nobody wants to remotely touch each other . Everyone gets their own cotton sleeping bag effectively - a bit like sleeping in a tent
It’s just a whole different way of seeing bedtime
Just like some folk let their kids cry to sleep
And some co-sleep, there’s room for more !
Ps - my expereince
My kids at different ages fight to have a sleep
With mum , stay up
In theory own bed reading / bunk
In with a sibling and listen to a good audio book together / sneak into a siblings bed because they think they have a better one and sibling got to sleep
With mum
It is musical chairs but it works for us !