Replying to @Brkdncr@lemmy.world
It’s only really the hyper developed countries that are experiencing the massive drop off in birth rates, so immigration would actually help this problem significantly.
Also, the lack of immigration in Japan is as much a matter of policy as it is everywhere else. Their government heavily discourages migrant labour (due in part to cultural racism), which has made their plummeting birth rate much more of a problem than it needs to be.