As the Japanese population shrinks, Chinese, South Koreans and Vietnamese arrive in growing numbers
https://www.scmp.com/week-asia/society/article/3018660/japanese-population-shrinks-chinese-south-koreans-and-vietnamese
I guess we can't afford to exclude Koreans, though many SNS users in Japan hate everything related with Korea.
Amid more than 400000 people are disappearing from Japan every year, we have to find better ways to let more foreign people live in Japan.