I would guess that Japan will have to import more foreign workers from SE Asia and China for labor, housekeeping, nannies, etc. Basically, they’ll have multicultural problems.
Robots!
No Sh*t! What you are you saying is Japan should be colonized by Chinese that will transform it into another Chinese colony and kick out US military presence from Japan. Never say that again! Just immagine millions of Islamist immigrants invading US transfroming US into an Islamic state. Do you want that to happen?