Doctors don’t enforce shortages. No one is stopping new medical schools from being created, it’s just not a trivial thing to do.

I’d actually argue that physicians haven’t yet fully grasped their power. Historically, many docs worked in independent clinics or small practice groups. That made them subject to antitrust law when teaming up to negotiate en masse against a large insurer, for example.

Today, with all of the consolidation over the past decade, many have become employees. This has made them less powerful in many ways... except, now they can unionize without any of those old antitrust concerns.