Teachers be like “I’m more than happy to accommodate students with mental illnesses or disabilities. I just don’t excuse any absences, offer extra credit, or accept late homework. Also my only office hours are off campus on the last full moon of every other month”
Also, when I was in college, the student health center was unable to write any doctor’s notes for missed classes. That was baffling and infuriating enough when I was simply down with food poisoning, since we could only miss four classes in any given course without failing. I can’t imagine how bad it would have been had I had a chronic illness or something.