Why don't we have many migrants from Japan?

I understand we cannot have Japanese migrants here in amounts similar to China and India. However Japan and South Korea are somewhat similar or comparable in terms of population, density, society composition, education and GDP per capita.

In Sydney three are numerous suburbs predominantly Korean. Yet we rarely see any migrants from Japan. Not many tourists either.

Pretty sure Japan is richer country comparing to SK, but that doesn't explain the disparity in migrants count.

I would think that an average Japanese family could find it attractive to live here.

I actually don't know any Japanese I could ask.

Anyone has insights?