I don’t think they were arguing it was a bad or boring book — I think they were arguing that most students don’t have time/energy to do all that reading for all 5 or whatever classes they are taking every semester. I certainly didn’t.
I came to love all the books I read in uni philosophy and literature class, but I am incapable of enjoying them on my own without being shepherded through the context and meaning that make them interesting, sadly. Or rather it’s work I just can’t bring myself to do at my own leisure.
It’s amazing what a good professor can get you to do and love.