Under a literal or charitable reading, it's not a problem. It's making the point that systemic racism can pop up in a number of places on a map of the educational landscape. That's fine. It's true. It's not saying that those places themselves inherently constitute white supremacy culture.
However, this all hinges entirely on the reading being charitable or at the very least literal -- and if there's one life lesson that my interactions with others keep hammering home, it's that people are not generally literal or charitable. People are fuzzy association machines. Literal meanings can sometimes protect you in a court of law or court of academics. Charitability can protect you among friends. Absent those two narrow, tenuous exceptions, that paper gives wokescolds permission to label any of a dozen core aspects of teaching as "white supremacy culture," insofar as school administration allows it to do so, which by my estimation they absolutely will.
I sincerely hope this fear is misplaced.