And various types of consulting. I know a few semi-retired people in the IT realm who retired on the early side and still do some work on the side. The key is that you're sort of doing your own thing on your own schedule. Which doesn't describe most people at the average tech company.

Certainly for senior people there are probably one dayish a week roles that don't even have to happen every week. But now you're still essentially talking about being a consultant.

Those jobs have a fixed supply of graduates set the the Bar and AMA accrediting medical schools (and law schools but that is less clear to me, but anyways law school is very prestige based so kind of moot if a 3rd tier law school expands enrollment). Other fields have no body policing the incoming employee population.