After all, the Web means

An end to credentialism. Now any amateur physicist can contribute in their spare time. Smoother, better peer review processes. Cheap, universal distribution.

Physics (and STEM more generally) is a terrible example of credentialism. Almost all original research in STEM is not done by amateurs (e.g. the uncredentialed), with good reason.

The higher education bubble is likely going to "pop" eventually. (Maybe when employers realize that taking Coursera classes is a positive signal of

Yeah, I am sure enough about this not happening that I am willing to place bets. There is an enormous amount of intangibles Coursera can't give you (I agree it can be useful for a certain type of person for certain types of aims).