Star Trek imagines that even in an age where computers have universal translators, people will still learn languages for "personal development" purposes, or to honor their ancestry, or simply to not have to rely on a computer for a regular activity. Ideally, the translation ability of AI should make it easier for us to practice conversations in new languages, and actually encourage more language learning through total immersion without having to travel to a country where that language is the primary.

Whether Star Trek is aspirational or inspirational, I guess we'll have to see.