Frankly, a lecture is a lecture. And most times there is so much information to get out in one 50min session, and so many students, that questions and answers aren't really practical during the lecture, even though they're often "encouraged". Maybe a few questions is fine, but if there are many longer questions, it quickly bogs things down.
So, I actually think -- for lectures -- that online might be the way to go, moving forward, anyway.
The big value with in-person education comes from the rest of it: labs, discussion/recitation groups, hands-on learning sessions (thinking nursing, medical, law practicing, etc.), and small group or one-on-one meetings with TA's and profs.
As far as suing, can a student who dies in a car wreck sue the University because they were on their way to a class? Of course not. There is some risk inherent in life. Now, you can try to prove negligence on the U's part, but that will be very, very difficult as the U will leave no stone unturned there, to make sure they do as much diligence as they possibly can.