Student who intentionally disrupted a class, using a bait and tape tactic to produce a clip that would embarrass the institution probably for no particular reason other than to boost his social media 'scores'. Yeah, I can see why supporting that student might not sit well with the administration. Especially since the language in the 'supportive' blog post is also hostile to the institution, and is apparently something the professor had been warned about previously.
Repetitive biting of the hand that signs your paycheck is a sure way to stop getting payed. As it should be.
He really derailed the class with his after-class discussion.

Can colleges even be embarrassed anymore when they shut down debate?
It seems like more of a high five moment these days.
Supporting undergrads who pay less $$$ than grad students never sits well with admin ya.
The old fool thought tenure would protect him!

Being 69 years old, they were probably looking to ease him out anyway.