They are absolutely the same problem. Because we can't measure productivity, we can't determine relative quality in an objective way. If we could, it would make the hiring process much more simple.

The question I have is, how is this much different than any other profession? How do we measure doctor productivity? What keeps me up at night is that it is very likely that the 90/10 crap to good ratio in software developers is probably the same ratio as surgeons.