These fertility rates reflect the individual decisions of millions of people, and millions of couples.
There are many interrelated factors, I’m sure, which have caused the decline in birth rates.
I agree there are many factors.
The economic issues are real for the “middle class” who has to pay taxes and pay their bills.
If you live on a farm and can put children to work at a young age then the children quickly become an economic asset.
If you live in a city and child labor is banned and your children will use resources (money as well as time) they are an economic liability.
That is why (imho) economic incentives are critical—and they must be very significant to make a difference.
If you want folks to have kids my proposal would be a twenty year income tax holiday for married couples who had a child starting on the day the child is born—that goes away in the event of divorce. Additional children would restart the clock.