My experience learning Japanese, and more importantly living in Japan, has convinced me of the complete opposite: that linguistic differences are almost entirel

My experience learning Japanese, and more importantly living in Japan, has convinced me of the complete opposite: that linguistic differences are almost entirely downstream of cultural differences. The things you initially think are unique to the Japanese language are actually preserved fully when speaking with Japanese people in English (bearing in mind that a Japanese person who learns English fluently will inherently be atypical in various ways), and the experience of speaking with a Japanese person in English is far more "Japanese" than speaking Japanese with someone who has never lived here.