>But that said, I don’t believe this author is complaining that students generally don’t attend lecture. They’re complaining that absenteeism has increased, implying that it has increased substantially recently. And that this sudden increase in the delta is a cause for concern.

From experience on the professor's side, the problem isn't the brilliant students who show up to one class and ace the exam like everyone in here seems to have been. The problem is the students who miss most lectures and get 50% or lower because they (and, increasingly, most students these days) don't actually understand how to study from a textbook.