The number of newborns in Japan fell below 700,000 for the first time since records began in 1899, according to government data, as younger people are reluctant to marry and raise children due to economic concern and a society that still adds extra burden only on women.
So if everyone only had 1 kid or 2 kids, then population might stabilize and start shrinking. Then we just gotta keep it small enough to maintain a good standard of living. Of course all of us old fucks have to die.