From my experience it works fine if it's one class that's doing it. If multiple classes are doing it then like you said it's literally a couple extra hours a day watching lectures and most students end up skipping them, forcing the instructor to end up teaching during class time anyways.

We’re discussing university, right? It’s supposed to be a full-time effort, at least for a normal pace undergrad or any post- graduate program.

For secondary school, I do agree with you - homework load can be problematic for some students. But at the same time, my honors classes all came with hours of homework and I’m not sure I would have been as prepared for uni without it.