I agree it depends on where you are, though I'm not sure about the "American" categorization.

I was in Seoul where small talk with strangers was completely weird... then I went to a different city in South Korea, Busan, where people would chat you up all over the place (waiting in line, in a street food stall, at the sauna, etc).

I later learned that Busan was a city of refugees in the Korean War where the entire country was pushed into a single city - people had to learn to live closely packed together and cooperate, and the culture stuck.

I'm an introvert and prefer to not have small talk, but as a tourist in Busan, it wasn't that bad (fun, actually) to randomly hear about a stranger's daughter's upcoming wedding, completely unprompted.