It’s about culture, not economic conditions. A number of American sub-cultures that are more educated and wealthy than average (Mormons, Muslims) also have above-replacement fertility rates.
It is culture but it's not the pro-individualism enlightenment parts of Western culture that made us great. There's so much anti-natalistic culture to fix (and a little bit of economics)
- make housing cheaper
- fix education so people can start their careers and adulthood earlier
- pass safe harbor laws so that parents and feel safe leaving their kids at home, or letting them take the bus
- also economic incentives help, beef up people's social security if they have kids
> fix education so people can start their careers and adulthood earlier
People can only learn so quickly; you're not going to give people a college-level education by age 15. Modern society requires more education to be productive than past societies, but this is at odds with human biology.
> pass safe harbor laws so that parents and feel safe leaving their kids at home, or letting them take the bus
This is only a problem in the US, but birthrates are low in all developed nations.
Some economic incentives might help a bit, but they're not going to have a dramatic effect: people simply don't want to have big families any more. Kids are a lot of work (and expensive, even with those incentives), so people like to have 1 or 2 and concentrate all their attention on those. They don't want 6 kids.
Don’t forget that those societies also impose heavy obligations on men. Are secular women, many of who are stuck both working and raising kids by themselves without men supporting them, happier on average? I haven’t seen any data to suggest that’s true. Indeed, Mormons are happier overall than other groups: https://news.gallup.com/poll/152732/religious-higher-wellbei.... Maybe there’s a big gender gap there but I’m not aware of any data to support that notion.
