Watching lectures such as this and those in my own field I have often thought that college professor/lecturer is one of those jobs which don't have much of a future.
By that I mean that there is no reason for 95% or more of university faculty to exist. Why attend a lecture on linguistics by a comparative nobody if you could tune into a lecture by (the young) Chomsky? The future is for a very small number of great thinkers and teachers to dominate. Imagine taking a course on HIV with one of the men who investigated the disease from its first onset in America in the 1980s--people like Robert Gallo or Robert Redfield. Or a course on English Lit with Heaney when he was alive.
There is no limit to the number of students such people could have. Most lecturers/professors would become redundant, though a small cadre could be kept on to do tutorials, mark papers etc at local level. That model is perfect for English speakers, a little more complicated for students who don't know English, though increasingly English is becoming the lingua franca at third level internationally.
Actually, elements of this have developed ad hoc already. In the US it is quite common for an undergraduate to reach degree level without ever having been taught by any of the tenured professors in his university--all contact is with Teaching Assistants, part-timers and non-permanent faculty. That's not a good model--students deserve to be taught by the best, and that means the best anywhere.