It's not like the criticism in this case is particularly esoteric: Literally the first explanation is that the proposed classes don't encapsulate single concepts. That's the theory of the first course you'd get about this in school, or if you're self taught something you'd see within the first 30 minutes of casual googling about the subject.

I think it's fair to question what is going on in the article if the mistakes made are of such a basic nature.