I think this sort of thing is a result of liberals trying to move farther left, but falling off a cliff because they have no understanding of class.
edit: I thought there was a whole thread, but to see the full context you have to go to the student's account and see the ensuing drama. This singular tweet is pretty fine on its own.
The email (which isn't a carefully-worded PR piece, btw, it's personal mail) says that the representation of minority cultures is not the "first priority" when devising the syllabus, NOT that the course isn't intended to represent them. I.e. choosing what's on the syllabus is about themes, ideas, contents - not who the authors are, which smells like descriptive representation to me.
We need more context - and so does the student. You can't judge a course by skimming the syllabus, much less try to take down the professor. How the hell do you know what the class covers well before you even take it?