OOCs expand the audience for education to people ill-served or completely shut out from the current system, in the same way phonographs expanded the audience for symphonies to people who couldn’t get to a concert hall, and PCs expanded the users of computing power to people who didn’t work in big companies.
Those earlier inventions systems started out markedly inferior to the high-cost alternative: records were scratchy, PCs were crashy. But first they got better, then they got better than that, and finally, they got so good, for so cheap, that they changed people’s sense of what was possible