I completely understand what Amanda and Raisa are getting at. I do believe that there are a large number of students who do turn up to lectures or classes that are on site and get distracted by being on social media anyways. Why do universities allow this to happen on their own time and costings. If a student cannot or does not want to attend class any given day, having all the content available online would allow the student to not miss anything.
Regarding class discussions, I have seen universities set up community chat groups discussing anything from the lecture content, to assignments even to potential job opportunities in any given field. Obviously there are some degrees that it is required students participate in practicals and labs. But for the purpose of this discussion i believe a university could offer the majority of business, law, some engineering, and other research based degrees online with 1-2 organisational tours for any practical information.
Lastly, universities take up a ridiculously large space (such as libraries, sporting fields, halls, etc which obviously students use... but removing these aspects from a school, a university could severely cut costs from operating out of one building and thus selling off acres of land. From an image point of view, the school isn't attractive for a student to participate on campus, however these activities such as sporting games that a univeristy could choose to not offer could be contracted out to other clubs or organisations with close partnerships.
Bottom line, there is a large percentage of students who turn up each and every week to classes that aren't 100% mentally focused and result in wasting both their time and the universities time. Both the student and the university could be far more productive by offering the entire education service online for consumption at a time best fit for the customer