The study suggests that there was sufficient literacy in 600 BC to have written the early books of the Bible at that time.
Previously one argument against that early date was the lack of widespread literacy.
The “Bible” as opposed to components of the Bible was created by editors over a long period of time: first Jewish priests, then Catholic ones. Wikipedia:
Rabbinic Judaism recognizes the 24 books of the Masoretic Text, commonly called the Tanakh or Hebrew Bible, as authoritative.[1] Modern scholarship suggests that the most recently written are the books of Jonah, Lamentations, and Daniel, all of which may have been composed as late as the second century BCE.
I read an article that the earliest New Testament found was Greek. I would imagine first century Christians had the original Gospels written by the Apostles. I think the jury is still out on who originally assembled all the books and letters.