Rightwriter, the only wrench thrown is the wrench in your question. (No offense intended.)
Of course, the Italians and Persians are a continuation of the genetic lines of Rome and Persia, but they are completely different today culturally and are entirely different nations in every aspect. We are a continuation of the Jewish nation of then, as we are currently. Lack of sovereignty doesn’t mitigate the status of a cohesive nation or people. Though we are international and broadly diverse, we maintain our identity and distinctive existence as uniquely Am Yisrael.
As far as Languages go, they constantly change even within individual nations. Just look at the 2500 year linguistic histories of Germany and Britain. Our language evolved too, just like others. Notice how the words in Navi are different than Toras Moshe and evolve even from sefer to sefer.
Lashon Kodesh is indeed the original language, though it may have already evolved into many dialects by the time we stood at har Sinai.