Yeah, I get that people read/work at very different speeds, but I’m deeply skeptical that any (much less virtually all) of the undergrads I taught could read scholarly monographs at a speed of 125+ pages per hour. And then didn’t need any time beyond that to think about what they’d read, whether they agreed, how it related to other texts in the course, etc.
For what it’s worth, I’m not really blaming the students – just explaining why, even in highly selective schools, lots of the work getting turned in is unimpressive. Most students most of the time just don’t put in the effort it takes to do academic work really well, even when they have the ability. Seems true in the workforce as well, so I don’t think it’s unique to college.