I recently read David Lindley’s “Uncertainty”, a historical account of the persons, places, and conflicts of early to middle quantum theory that accords with the in-fighting and parochialism that you decry in the humanities.
I think academics are people who follow intellectual fashion, either because they genuinely agree, or because they see it as necessary/helpful for becoming “successful”. The fact that most PhD’s begin their doctoral studies fresh out of college makes them ever more likely to fully (and gratefully) accept whatever the “dominant ideology” of their advisor/school/field. BTW, I was in my mid-50s when I received my PhD (after having obtained multiple Master’s degree when younger). In short, while I share your hope for more balanced approaches to “educating” students, I am not especially hopeful that it will occur anytime soon, at least within traditionally-oriented departments. A possible source of good news is that the rise of inter-disciplinarity lead to less ideology.