Quite the mystery. Because the spine of the hinge is actually higher than the edge there. Something to have chipped off quite an area without touching the spine seems unlikely. Could be QC. Will be interesting to see if there are other examples to point to QC.
I doubt it looking at it from a small screen but is that real carbon fiber or a fake finish? If it were real any any of the fibers are exposed the certainly could wear away at it.