Its the OPPOSITE of neoliberalism that caused degree deflation and collapse of the humanities.

Neoliberalism would have placed a higher value on humanities than neosocialism.

Socioeconomic engineering:" thou must have degree", combined with student loans, is neosocialism. They dramatically re-engineered colleges (with a 1000 year history) to meet a new socialist ideal of more equal pay for all social classes. The economics doesn't work- it's painfully expensive.
degree quality deflation was NOT what the end customers (employers) demanded. It was what the product themselves (labor) demanded under neosocialism. Because labor is the product, it's an unusual market... the labor is buying their own ticket to a career. The university was supposed to ensure the product remains high quality. They failed dramatically with their education theory of tabula rasa and "pay to win". Yes, the SOCIALISTS are the ones who believe in pay-to-win. "Throw enough money at the student and they will have equal outcomes". The neoliberals are the ones promoting ways for students to stand out- internships for example. They are winning the argument but not for the reasons claimed.
humanities are generalist degrees- degrees for raw thought without much clear application...employers have increasingly standardized ordinary labor (who cares if you know Shakespeare) and increasingly demanded complex, specialized knowledge of the leadership roles.
For example, Shakespeare and Aristotle used to make a big difference for articulate leaders, but now we have these specialized courses and leadership tracks for managers in the business school, social sciences, or military academies, which reduces the relative value of Shakespeare. This is Weber’s iron cage of rationality and is true under communism and capitalism.
Social class engineering. Skill with the Humanities used to separate people into higher social classes. The Socialists wanted to end that. So they changed the humanities into DEI and critical studies. That ruined the humanities. They are collapsing due to the social mission of homogeneous social knowledge- that is, ghetto knowledge is of equal status to Shakespeare.