Languages are chosen for many different reasons, which are not all obvious. Also it sounds like you're conflating language and culture, which are related things

Languages are chosen for many different reasons, which are not all obvious. Also it sounds like you're conflating language and culture, which are related things but not the same thing. If I know French, I can communicate with people in countries on three different continents, and the usefulness of a language trumps all other reasons for choosing a language. I've been in a few weird international groups, with people from dozens of countries present, and everyone communicates in French and English (a mix of both really), even though many of the people are multi-lingual, because everyone present knows at least a few snippets of French and English.