The Japanese are incredible even if more than 40,000 elderly die alone in their homes each year and are discovered decaying sometimes many months later. The loneliness and death not seen or heard of only to be reported much later is the downside of these amazing people.
Things got to change in Japan. They must import more people. If they wish to not have or raise children, they must fall to China or North Korea. Maybe that’s not a bad thing? Rome didn’t have families, were replaced by barbarian hordes.