To locate microaggressions, you would need a microscope and more than a touch of paranoia.
However, I think it is barking up the wrong tree to try to psychoanalyze this grievance-collection and grievance-manufacturing by the most privileged and indulged kids in the world. No reasonably balanced person reacts to such non-events. It is a fad, like hula-hoops. Faux outrage, microaggressions, and hate hoaxes are all the rage on campus this year. One might almost imagine that the ignorant kids have nothing to study. What it's really all about is cry-bullying, a manipulative power tactic which only works on spineless women and beta males.
Those are the same administrators who will buy their 3 year-olds Cocoa Puffs at the supermarket when they cry. Same stunt, same result. Too many spineless people out there who are afraid of saying "Shut up and grow up" the way normal people would do. Or, in the campus case, "Shut up and get back to your differential equations."