You spoke with "a lot" of people in Japan on the subway during your daily commute? I am stunned here. Can you provide more details? (Years / location / line?) I find this very hard to believe. Metro trains in Tokyo and Osaka (and suburbs) are basically silent except very late when people are drunk, talking with their friends.

Kyoto 2005 to 2008. Mostly Kintetsu and subway (mostly between Kyoto and Nara). Later keihan from demachiyanagi to shijo kawaramachi. I am the one who often initiated the conversation (apart from some osaka bachans who did initiate. I'm using that term of endearment not criticism despite their fearful reputation Osaka bachans are great). There were also significantly less tourists back then. Made a few friends with whom I still stay in touch. Also met my first wife like this.

I had the same experience of meeting people in the same way in Shanghai in 2004 (bus and subway). And before that, in France，the bus line I took near my university was filled with students.

I spoke with Japanese people on the subway. They were very friendly to this gaijin.