People choose to have fewer kids as they get richer, it's not about living conditions like so many people like to claim, otherwise poor people wouldn't be having so many children. Even controlling for high living conditions, like in Scandinavia, people still choose to have fewer kids.
Housing seems to be a pretty common issue that doesn't prevent people from having kids but if it delays (which it often does) it does the same job of dropping birthrates. I wish people would stop acting like it's only a wealth issue. Like oh if people get more money they no longer want kids....no
It seems much more likely that humans don't have a particular impulse to have children because their instincts were designed for a world without birth control. Having children has become uneconomic, so people stopped. There isn't a natural instinct to raise alarms about that (which is what evolution would tend to do) because historically that just wouldn't have mattered. Both because people were poor and because sex used to imply children in a way it doesn't now.
The house thing is really a red herring. Sure we'd all like to own a house and being wealthy is better than being poor. But in a literal sense - not necessary and for almost all of our evolutionary history people have been reproducing without any wealth at all. The stats actually seem reasonably clear that it is exactly wealth that is blocking the children, despite the excuses that people come up with.
A real boon from chance that is unlikely to last, we're probably lucky to be living in this era before evolution starts kicking in and pushing us back towards overpopulation. Which will happen in a few generations.
Tell that to a good bunch of people I know who feel secure about their living situation well into their thirties and then of course that 3rd or 4th kid or even 2nd kid they might have felt comfortable having never happens.
What was the historical standard does not matter today in this context. One set of my great grandparents had 8 kids in an abode smaller than mine today. Yet I do not have a single one because where would I put it. A room where i have to strip the walls?
>before evolution starts kicking in and pushing us back towards overpopulation
societal evolution will work quicker than biological evolution ever will. Most of the families with lots of kids here in western europe are conservative muslims.
Chalking it up to choice seems a bit unfair. I suspect lack of access to birth control probably plays a part.