I see two issues with that approach, even though it would have a lot of benefits:
A lot of people aren't good teachers and aren't particularly interested in teaching. While there are plenty of people like that who are already professors, I think the problem would get quite a bit worse if teaching becomes the job of even more people (including many who never got into their field wanting to teach in any capacity).
Existing universities produce significant value through having research so closely linked to teaching, and though having multiple different disciplines all easily accessible to one another. Again, there are problems with this approach, but a pure apprenticeship model would run the risk of siloing students off the newest work and from adjacent disciplines that might be valuable or interesting.
A mix of university-style teaching and apprenticeships (or paid externships) would probably get the best from both worlds. I think some fields already do this, or at least something close to it.
I see two issues with that approach, even though it would have a lot of benefits:
A mix of university-style teaching and apprenticeships (or paid externships) would probably get the best from both worlds. I think some fields already do this, or at least something close to it.