Because Americans are sold bullshit narratives about university educations intended to justify the mountains of debt required to finance the lifestyles of the people who run those institutions.
> The shift to the right coincides with a decades long attack on academia and intellectualism.
This is a comforting narrative for leftists, but it's objectively false.
The attacks on academia and "intellectualism" (isn't it interesting how progressives presume a monopoly on this, just as they do on progress?) are a reaction to the exploitation of the academy as a tool for political indoctrination.
Individuals with openly right-wing beliefs are personas non grata on faculty, in administrations, etc. There's a reason for that. The left is desperate to maintain its stranglehold on one of the major sense-making organs of the culture - and its stranglehold on the ability to socially engineer the next generation of educated professionals.