> Japanese ppl don’t like touching each other they don’t really shake hands socially but they bow when saying hello and good bye

Yet they stick to each other like sardines in a can when they take public transport every single day in Tokyo and Osaka - and we are talking about dozens of millions of people who transit every single day. That should be the primary mode of exposure especially since masks have completely run out in Japan for months.

So, unlikely to be a good explanation, sorry.