Yeah it doesn't help there's like a 1:3 female to male ratio, even if they wanted to meet replacement rate, thanks to one child policy incentivizing parents get abortions or committing infanticide until they had a son, they don't have enough wombs to go around. A lot of angry desperate young males though, which is causing different societal problems, kidnappings of females from other countries, etc.

This cuts both ways. The problem is that the US is already developed and the lower fertility rate will only keep up what they have. China has a lot of people who are, in this generation, coming out of poverty, and this will continue for decades, until the possible downsides of fertility show up.

Moreover, the US is changing its immigration policies exactly at the moment they need it most, which seems to be another tragic mistake.