Modern linguists don't often think about the implications of our mythology of the Tower, which is depressing but I have a remedy. I would like to first start with a sad biblical view of affairs. Generally the story of the Tower of Babel is either seen as a literal linguistic history of the creation of a variety of different languages, or rather a metaphorical story about a society who's technology has become so advance their communication suffers. The latter is a very prophetic interpretation, seemingly telling the tale of time about the progression and eventual destruction of a society. Although this may seem profound, it can be hard to know if this interpretation is just prescribed by us or not (reminds a me of psychoanalysis coincidentally). For my alternate history to be described we all must reject the biblical stories, as Slayer say in New Faith, "I reject all the biblical views of the truth / Dismiss it as the folklore of the times."
Many many years ago before the time of Proto-Indo-European existed a sacred language named Edenden Adámm. This language was spoken for approximately 700 years, although the Tower was built 500 years after it started being spoken. The Tower is not a story of communication or pseudo-linguistics or anything else, it only signifies the beginning of language change. Only one language existed before the Tower with one exception. After the Tower new languages were spoken on this earth, including that of Basranti. The one exception being Neflim (or the language of the Nephilim) which existed before the Tower as a creole between the angelic language and Edenden Adámm.
This is our linguistic history, and we must accept it. We cannot let our psychoanalytical overlords consume our already feeble science. As Maynard James Keenan sings in Schism, "There was a time that the pieces fit / But I watched them fall away / Mildewed and smoldering / Strangled by our own coveting." I only ask to save our last science and to not forgive the art.