This article, and many (not all) of the comments here, are really missing an important point: that if you don't view a bachelor's degree as vocational training, but rather as the education proper to any free person---i.e. the liberal arts ideal---then you would expect a lot of people with at least bachelor's degrees working in fields that don't, on surface, "require" them.
The idea of college (=university) students having a specialisation (a "major" area of study) is not by any means a new one, but the idea that this tightly corresponds to one's career and serves as a sort of vocational training program, that's pretty new. Schooling of that nature used to be found primarily in apprenticeships and vocational schools.