Tele-medicine could be a part of this - I have seen a rise in online services where patients can receive a diagnosis and some prescriptions by text/video chat with a doctor or nurse. I think this will likely continue expanding, perhaps even including decentralized, robotic surgery (see Intuitive Surgical), though I doubt this will ever be fully automated.

not op, but i think nurses will be able to subsitute doctors in many cases where the diagnosis comes from a fully-automated AI system. E.g. a CT scanner or blood test that prints out full diagnosis, prescription and procedure etc at the press of a button.

One rationale (well before/without AI) is that medicine operates at 2 levels of hierarchy (doctor, nurse) whereas most fields operate at 3 levels (say exec, mgmt/expert, worker/employee), typically mapped to 2-3, 4-5, and 7+ years degrees in most countries.

It's been argued in many countries that medicine could get cheaper if only 10% of doctors-only gestures and decisions could be delegated to some 4-5 years intermediary medical degree, above nurse and below doctor. In reality it's more like 50% of doctors' work could be offloaded. Which also has the benefit of mechanically addressing the general lack of medical doctors in rich countries with aging populations.