I was thinking more like text books. Text books authors are generally much more wordy than they need to be because the publishing industry and academia awards length. But with that said, I kind of disagree with you a bit on biz school work. I'd say a quarter of most HBR case studies are fluff. I don't mean throw 12 on the floor and 3 are fluff, I mean, take a 12 page case study and 3 of the pages are not adding value.
Articles are even worse because the pay is often by the word and there are min lengths to get into the print edition.
Speaking from experience. I actually wrote a book for a major publisher and the main metric that determined how much I got paid was page count. We had a page count decided before the first word outside of the proposal was written.