Nah Japan rejects a lot of people even for work visas, also the requirements for maintaining the work visa can be extremely burdensome. You are underplaying the amount of bureaucratic hurdles that the average person will in fact face.

This nation has always taken in at least some percentage of less well off immigrants. It's against tradition to do otherwise. I don't see why we should render the second category non-existent, or why that is some inherent good that everyone should agree to be the case? Am I allowed to believe otherwise?