From Quillette, some confirmation of a theory of mine:

When first published, Zinn’s book was a disruptive and influential text, which would have made it a wonderful teaching tool then—but circumstances have changed. I know this because my classes were all Zinn, all the time (even though his textbook itself never made an actual appearance). In my head, this made my classes all about counter-narrative. But to my own students, my classes were just plain old… narrative.

Much more at the link.

Also:

There are two values in conflict here. One is the idea that engaging with an opposing idea makes the other idea stronger. The opposing position is that by engaging with other ideas, you make your own ideas stronger. Gay chose the latter approach, at some risk. Indeed, the prevailing logic among many is that by debating Sommers, Gay became just as “offensive” as Sommers herself.

It is hard to imagine anybody with more progressive bona fides than Gay, yet even she still feels somewhat apprehensive about engaging with ideological adversaries. This trend toward freezing out controversial ideas is a deadly threat to any trend in academia that even comes close to my own teaching approach. That career counselor was absolutely correct to recommend dropping any detailed discussion of my methods in my cover letter.