>> From what I can tell, there's very little enthusiasm for online education, on the part of either professors or students.
This isnt surprising -- you are probably polling people inside the system -- what about the many more people who cant join the system? I'll bet they have a very different opinion.
The US educational system, especially graduate education, is a game of money. Even those graduate students who are on grants are only the lucky ones who don't have sufficiently large family obligations to fulfill and can therefore stay on a graduate grant. Think of how many people need to work at their parents' shop, have to take care of a grandparent, sick elderly parents at home, those who are also caring for younger siblings, those w/o sufficient disposable income to sit around at quads sipping lattes.
Consider all the people who couldn't pay to play that game. I'm sure they would love an alternative.
Also consider the opposite problem -- people with money who do not want to take off two years (without income) to get a graduate degree, or worse, move their families to one of several key cities with top universities. They would also like an alternative that is mostly remote.