I think it's a combination of a CS degree being slanted more toward research than preparation for a career as a software developer, and not everybody is cut out

I think it's a combination of a CS degree being slanted more toward research than preparation for a career as a software developer, and not everybody is cut out for it, temperamentally. Particularly the latter. A lot of people break out in hives at the thought of spending the next forty five years glued to a computer monitor.