The switch to online learning IMHO would lead to a 'winner-takes-all' market for professors/teachers.
To simplify, if you're attending class at a top university you get a top math professor, if you're attending a school ranked at #1000, then you have to settle with whomever they can get. However, in an online setting, why wouldn't all the students just use the top online material? And in that situation, the top professors become more valuable (since students of many universities not only want access to their lectures, but also can actually get them), but the majority of median-quality professors become expendable.