If you read your own link, you’d find that Baumol’s hypothesis is that cost disease led to an increase of professor salaries… which is not reflected in reality.

If you read your own link, you’d find that Baumol’s hypothesis is that cost disease led to an increase of professor salaries… which is not reflected in reality. Real professor salaries have decreased (not increased) over the relevant time period, mainly because universities have shifted from tenured faculty to untenured adjunct, who work on semester-long contracts.