The Ashurai people have survived to the present day after the genocides carried out against them by the Romans at the time of Eashoa (Jesus) the Messiah and the Muslim conquerors of Mesopotamia and the Holy Lands, after the 7th Century. Eashoa (Jesus) read the Book of Isaiah and other Scriptures at the synagogues in the Ancient Aramaic language.
Why hasn't anybody written the history of the Ashurai people? Because it is only in the interest of the Ashurai to write the history of the Ashurai. If they don't write it, for whatever reason, why would anybody else write their history? And how can the descendants of the Ashurai, who rarely call themselves "Ashurai," expect anyone to accept their survival as a nation from antiquity, if none of their scholars or learned people bother to write about it?
Of course, there have been books written on the subject of modern-day Assyrians -- the Atourai, as they call themselves in Syriac, but no one has dealt satisfactorily with their survival and actual descent from the Ashurai of Nineveh. No one has produced acceptable scholarship in this regard for the Western world to include within their universities and official libraries. In fact, the Western scholars and the Western Churches reject the notion that the Ashurai nation has survived.
No one argues about the Jewish survival as a nation. The Jewish people have maintained their culture and heritage, and they've suffered more because of their religion than the Ashurai and other nations of antiquity that followed the Apostolic Faith.
However, many people haven't retained their national character sufficiently to be called by their original name; for example, Italians don't call themselves Romans and the Norwegians don't call themselves Vikings anymore.