This is exactly what academia is supposed to be, and it doesn't work. (Notably, it didn't work for Einstein, who didn't get let in until 1908.)

This isn't true. Until 1905, Einstein was a graduate student (a very junior "insider"). He was still under 30 in 1908 when he was given a lectureship, which is a pretty plausible age to be given a teaching appointment. So that's three years spent outside the academy; not so very long.