Those countries are all below replacement level too though. This is a problem that’s affecting almost every country in the world, not just the US.
In fact the US has been able to avoid the problem for a while because of immigration but even that’s not able to keep the replacement level up anymore.
Why do we have to go to the extreme. The scandanavian countries are socialist/capitalist countries and they have one of the best living conditions.
Those countries are all below replacement level too though. This is a problem that’s affecting almost every country in the world, not just the US. In fact the US has been able to avoid the problem for a while because of immigration but even that’s not able to keep the replacement level up anymore.