Even though it’s a statistic you can find in many spots on the internet, like the CIA factbook and Wikipedia, TFR or Total fertility rate (the total children a woman is expected to have in her lifetime, across an entire nation, ethnic group, or religious group, etc.) is a misleading portrait of the drop in childbearing over the decades.
Take two countries with a TFR of 1.5, which is very low, below the “replacement rate” of 2.1. This would be 15 children expected per 10 women in their lifetimes.
Country A gets to a TFR of 1.5 this way with ten women: 5, 5, 3, 1, 1, 0,0,0,0,0.
Country B gets to a TFR of 1.5 this way: 2, 2, 2, 2, 2, 2, 2, 1, 0, 0.
One country has a robustly fertile subculture leading to 20% of the women bearing 67% of the children and half of the women remaining childless for life. The other country has most women having kids, but nobody has a large family.
When everyone has one or two kids, this is child-friendly in a very limited sense of the term. Everything is set up around the expectation that women will be mothers, but not too much and not for too long. It is a Nordic model and in fact they do look more like country B.
When a few people have most of the kids, things are more complicated and uncertain as to future fertility trends. Because the choice to mother in country A is so much more stark and binary, there’s less child-friendliness in terms of maternity leave or whatever, but the women who will have kids will “harden” and just have them anyway…up to a point.
While living in a world with easy birth control is very new in human history, purposely limiting the number of children for any number of reasons is not. By the way, America looks more like Country A.
Low TFR is a data point, but how groups get there is also relevant to understanding what a robust natalism would look like.