@mathyone, OK. But online courses don’t all have to have 10K students.
As I said before, I don’t see any reason to conflate online with scale.
And even if there is a huge size, there are more ways of teaching and assessment than the traditional American college method (of frequent assignments and tests). For example, the Brits base grades almost solely on year-end tests. There are lectures and some of unis have tutorials as well, but, outside the tutorial-based unis like Oxbridge, students can study however they want. Then grading is done, but results may not be known for weeks or months. It’s a system that is perfect for distance learning (and thus also online learning) and indeed, the University of London External Programme is both cheap and serves a lot of people all over the world (and have for about a century or so). It also counts a few Nobel Laureates among its alums.