So Mr. Traore must have read or heard something about the Egyptian origin of chevrons, but missed the debunking of this idea. He uses the term "genesis chevrons" - does that ring a bell with any of your research?

I looked through my bead books and there is a mention of chevrons found in Egypt in Van der Sleen's "A Handbook on Beads" (1967). But he debunks the idea that any were made in Egypt. Apparently, 2 chevrons were found at an Egyptian temple but they were traced to the Napoleonic era, when horses were stabled in ancient temples. The reins of horses and camels used by the Bedouins were often decorated with European beads like large chevrons.

I think everyone looking into the history of beads knows how easily beads were transported all around the globe, so just finding a bead at a site doesn't really prove anything about its origin. I guess it's surprising anyone would have concluded that the chevrons found in Egypt were made there.