I have wondered that. The other thing that's crossed my mind is that there is surely a duty of care on the institution to safeguard students from unprofessional and damaging behaviour from staff, not to mention that in an era where student fees are astronomically high students who feel they're being shortchanged academically are likely to complain.
I got the sense from that evaluation that the module Professor Ivy teaches was light on content and the students' assessment tasks were far from taxing. In the short term, students are probably delighted to get an easy high mark, but if they find that they're not well prepared for the next level modules and get lower marks as a consequence, they may feel differently later on.
Tricky area as the students are legally adults, but still young and impressionable, and financial dependence on parents during the student years has an infantilising effect.