In my discussion of the National Geographic impression of the history of humankind versus the Genesis impression, I may have given one incorrect impression myself. From 50-150 years ago, historians and prehistorians would have generally agreed that The early books of the Bible were not stories about actual people, but collective legends only, perhaps based on an occasional real figure or event in the dim past, but no longer historically reliable in any way. As historian Paul Johnson notes, both the Wellhausen (Critical Method, Documentary Hypothesis) followers and the fundamentalists had a comforting simplicity to their ideas: The fundamentalists that the Bible was always literally true word for word, the scholars that it never was.
While this rejective view of historicity is no longer the norm among Biblical historians and archaeologists, it is still widely held, especially among those who were educated in other fields years ago. The pendulum has swung again. Further texts have been found and read, sites have been excavated, and odd things have turned up. It has come along in fits and starts - finding records of high-ranking officials with Semitic names in Egypt in the 13th-14th Centuries BCE, for example gives weight to the idea that the story of Joseph is based on a real person. Alluvial deposits in the correct strata give credence to The Flood. Descriptions of alliances and covenants similar to those we find in the Abraham story not only support the idea that such a one existed, but also shed light on the meaning of previously obscure references.
Obscure references - that is the really telling part. The 19th C German school which taught that much of Genesis and Exodus were compiled much much later by priests attempting to retroactively justify the claims of the Israelites is now pretty thoroughly discredited. There was simply too much that people wrote down that they could not have understood, but preserved because they believed it came from God and had to be copied exactly. The heroes had feet of clay, and some passages actually undermine the later claims. They copied and preserved in honesty, emphatically not trying to make it any better than it was.