[aksss]

I think you're still missing the idea that after the growth phase which triggers a boom in population, that sustained prosperity after the growth spurt is when TFR starts falling off.

Look at any given developed society today (characterized by long-term peaceful stability and general prosperity, development of professional classes, liberalization of gender roles, shifts away from field work) and you'll see TFR falling below replacement levels. This isn't a "western" phenom, you can see it in Korea and Japan as well, for example.

It's simply practical economic decisions by individuals - kids cost a crap ton of attention and money, and when the risks of them dying have decreased (lower mortality due to medical care, less war/violence) and the obligation to reproduce is lowered (changing gender roles, birth control availability, women having options for professional careers), and kids are less useful as labor units, you get fewer of them. Predictably. Across hemispheres.

I suspect your examples are all "developing" countries, not "developed" but you've thus far only referred to nebulous regions and continents. Interested in a specific example of a developed country that has not exhibited this pattern.