The problem comes when these students start looking for jobs or grad school programs. MOOCs aren’t set up to give students the networking opportunities you get from interacting with faculty and staff in a physical institution.
The truth of the matter is that people go to these higher institutions for the networks you can build. Yea it’s great that you can get access to Ivy League courses online, but you can get comparable education from plenty of univerisites and colleges in the US.
Until MOOCs can replicate that experience, there will always be a severe limit on how they can help students succeed.