Having children is definitely going to be another "tragedy of commons". At an individual level, one has to sacrifice a lot in terms of time, money and effort to

Having children is definitely going to be another "tragedy of commons". At an individual level, one has to sacrifice a lot in terms of time, money and effort to raise children. Some people love that (myself included), some people would love to do that but do not have resources for whatever reasons (student loans, crazy work culture, expensive housing etc). But a lot of people simply don't want to have children and all the costs associated with raising them. And that "selfish" attitude worked over the past 2-3 generations - why go through the hassle of raising kids when the government will anyway provide you pension and assistance when you get old? The costs of kids are privately born but the benefits are socialized in terms of taxes and welfare programs. And now you are looking at South Korea with a 0.7 TFR, with other nations not far behind. It will be interesting to see how South Korea and Japan deal with it. A range of outcomes are possible - a "Ship of Theseus" scenario with these cultures getting slowly replaced by immigrants, awesome future based on awesome robots, dystopian future based on overhyped AI tech, complete collapse of social programs as the young refuse to care for the previous generations who either preferred partying or were worked to bone by their corporate culture, or a soft landing where the society actually get its act together.