Earlier quoted context omitted.
Not just 'the West'. https://www.abc.net.au/news/2023-01-21/chinas-population-is-... https://www.theguardian.com/world/2023/jul/26/japan-populati...
Zeihan (geopolitics celebrity dude) talks about this pretty often. It goes hand in hand with urbanization. When you're on the farm and especially when child mortality is high...you have lots of kids as they're needed for work. In the big city, kids are just a costly burden, so people have a lot less. All the countries that jumped into urbanization are in this boat. China, South Korea, Germany, Italy, and Japan are al…
The dynamic is that when markets are expanding, it makes sense to invest in the future, because you can capture a portion of the expansion and the reap indefinite profits off of it. When markets are contracting, your incentive becomes to grab as much of the pie now before it shrinks. This tends to make firms...well, militant. The incentive to cooperate only appears when people weight the future more than the present, giving value to future interactions; otherwise, the incentive is to kill off your rivals, take their stuff, and hide the bodies. Thus, during a contraction and in times of scarcity people tend to become raiders, scavengers, and conquerors.
To protect themselves against raiders, scavengers, and conquerors, people tend to band together into larger groups. Thus a hierarchy emerges - weaker groups pledge fealty to stronger ones, which in turn protect them from other strong groups that have not pledged fealty, and so on. Usually you get war in the meantime, but feudalism is the peace treaty that arises out of that.
Interestingly this dynamic tends to play out within the capitalist system. When an industry reaches maturity, usually there's a shakeout with a price war where many of the weaker companies go bankrupt, and then the savvier-but-weaker get bought up by the bigger ones, and so on until you have a few megacorps with hierarchical organization. The purpose of managerial capitalism is as much to defend firms against competition as it is to increase efficiency. In many cases, they are significantly less efficient than they were as startups, but at least they have hoovered up all the competition.