[ayngg]

I'm not sure if it is the case that there is a commitment to nuclear family structure as it seems things are trending even further towards the atomized scale with more single parent households and many people delaying marriage and a family or even going child free.

I can't speak for elsewhere, but American society seems to incentivize against the factors that allow for high fertility. I think it is also apparent in Asia with the Sampo/ Satori generation phenomenon in Korea and Japan respectively.