Or the third option, different languages continue to be a thing around the world as they have been for thousands of yearsDifferent languages would continue to be a thing with option two. We're already well past how language used to be handled though. ~400 million people speak English as a second language and the only reason people would stop learning English as a second language is if a different language becomes more popular or if computer translation makes knowing a second language obsolete.
Although I guess it would be possible for everyone to just get really nationalistic and purposefully avoid interactions with people speaking other languages.
