In most of the world co-sleeping is just what everyone has always done. It was that way in Britian too for almost all of human habitation until the Victorians.
The Victorians started the trend for having nurseries, but even then their nurseries contained all the children in the household, not just one lone baby. Until that point everyone co-slept as a matter of course. There were a few exceptions, like the Kings and Queens who got a wet-nurse because the Queen was too valuable a trophy wife to be inconvenienced by feeding a child, but they were very rare.
The Victorians started splitting babies and children away from all sources of comfort systematically because they felt it was "character building". We would be horrified today at the best practice examples they tried to hold themselves to. No one would want a return to huge rooms filled with cots in orphanages where babies had been stolen by force from single mothers for their "own good" and then abandoned in a metal cot to scream for hours, with on-the-clock feeds and zero affection. That was how it was right until about half a century ago for many babies. What were we thinking???
The anti-cosleeping sentiment in society at large is still to some extent a hangover from that cold and cruel period. The period that forged the psychopaths who gained Britain an empire by being crueller and worse torturers than the natives.
Babies in cots might be normal now, but don't assume it ever got normal for good and worthy reasons. It didn't. It's a hang over of a past we don't want to repeat.
There is nothing wrong with cots, I am not saying there is. I think mothers have every right to sleep their baby in a cot if they want, indeed my 12 month old has moved to a cot (she chose to at about 10 months) but we as a society could do with dropping the scales from our eyes about why we really do many of the things we do.
The saddest thing is it's totally the other way in reality. Secure babies are actually the resilient, outgoing, balanced ones. That Victorian "toughen them up" mentality actually weakened them. Very sad.