A four year degree, for the most part, proves you can hand in coursework and pass tests. It does not demonstrate the ability to apply any of that education in the real world, nor does it demonstrate any ability to acquire and apply new knowledge outside of a classroom setting.

When you look at careers where the application of knowledge and critical thinking are vital to the work, all of them tend to have some kind of post-graduate schooling or follow-on apprenticeship where one works under an experienced professional, and even people in those fields can be pretty fucking stupid when it comes to things outside of their specialty…