Though on another thread (called something like why close until september?) an academic poster has said that there is a huge amount that can't be done online - discussion groups, team working etc - and in stem there is lab work, art/design studio time.
I think it also raises a conceptual problem, fittingly enough! - if all the content can be done online why run up such huge debts to 'go to university'? If it's for the social life and university experience (and realistically it partly is that which a lot of students are paying to get), going online hinders that because many students are, as we see, just going home to work. Clubs, societies, sports, presumably just stop meeting.