Why not get someone who's actually been harmed by this change in culture to write about that?
> being silenced
Nobody is being silenced by the students. What the students want is for professors to stop being assholes towards anyone that's not just like them, and are (correctly) pointing out various kinds of systemic bias, subjective opinions masquerading as objectivity, and instances where you have material that is disturbing or emotionally difficult for absolutely no good reason other than "it doesn't bother me, so it shouldn't bother you either".
When confronted with that, this professor's response is basically denial, writing off these complaints as irrelevant, trivial, or "pandering" (ignorant of how much society in general panders to his own perspective).
So, given that bringing this up directly will result in either being ignored, or being belittled or insulted, and the conversation shut down immediately... students don't actually have any choice but to complain.
At that point, the university overreacts because they're paranoid about being sued. Which is part of a larger cultural issue that has nothing at all to do with the students.
Funny that student activism that happened decades ago is considered a good thing (now), but activism by today's students is considered to be some kind of scary monster that threatens the whole of society...
As Judith Shulevitz wrote in the New York Times, these refusals can shut down discussion in genuinely contentious areas, such as when Oxford canceled an abortion debate.
More often, they affect surprisingly minor matters, as when Hamsphire College disinvited an Afrobeat band because their lineup had too many white people in it.
He [Chait] cites an anonymous professor who says that "she and her fellow faculty members are terrified of facing accusations of triggering trauma."
Consider that tweet I linked to earlier, from critic and artist Zahira Kelly, in which she implies that the whole of scientific inquiry is somehow invalid because it has been conducted mostly by white males.
In another instance, two female professors of library science publically outed and shamed a male colleague they accused of being creepy at conferences, going so far as to openly celebrate the prospect of ruining his career.
By the way, you seem to be the sort of person that scares him.
Rebecca Reilly Cooper, a political philosopher at the University of Warwick, worries about the effectiveness of a politics in which "particular experiences can never legitimately speak for any one other than ourselves, and personal narrative and testimony are elevated to such a degree that there can be no objective standpoint from which to examine their veracity."
Why not get someone who's actually been harmed by this change in culture to write about that? -You
I see why you think I would do that, but when I say that I don't think his fears are justified by the evidence presented and we should seek better evidence of a problem (presumably from someone else), I'm doing the opposite of "elevating personal narrative and testimony".
I think that the rather spurious grounds that he identifies for the fear motivating those changes is also important, particularly, it is important in identifying the source of the problem -- which is not, contrary to the headline, his liberal students, or even his students more generally.
> I once saw an adjunct not get his contract renewed after students complained that he exposed them to "offensive" texts written by Edward Said and Mark Twain. His response, that the texts were meant to be a little upsetting, only fueled the students' ire and sealed his fate.
On top of that, also, the groundless complaint that went nowhere in 2009 was from a student accusing the professor of "communistical sympathies" for not validating right-wing talking points on the housing crisis, and the result is that the professor is especially scared of his liberal students.
Cynical answer: because anyone actually harmed will be told to check their privilege.
Suspicious, realistic answer: because authority figures are always more scared of disruptions to their power than is warranted by actual conditions.