Man, Japan is really missing out here. They should listen to the wealthy western champagne liberals on HN who are outspokenly pro mass migration and yet spend most of their income to live in homes as far as possible from cities impacted by mass immigration, usually in majority-white suburbs with good safe schools and manicured lawns.
Edit: answering here to your comment below. Which statistics are you referring to? And why is resorting to the Hitler card on people who disagree with you your only argument? Let's address your vile accusations with facts from experts:
"Harvard political scientist Robert Putnam -- famous for "Bowling Alone," his 2000 book on declining civic engagement -- has found that the greater the diversity in a community, the fewer people vote and the less they volunteer, the less they give to charity and work on community projects. In the most diverse communities, neighbors trust one another about half as much as they do in the most homogenous settings. The study, the largest ever on civic engagement in America, found that virtually all measures of civic health are lower in more diverse settings."[1]
[1] https://archive.is/IrbAC#selection-445.127-445.686