Colleges are not a monopoly. All that is needed is for students to say "The marginal cost of switch from college A to college B is to expensive for what it gives me, so I am going to stick with college A". At this point, we have free market dynamics to offer the most attractive cost/benifit ratio. The problem that the article identifies is that college is simply expensive, and has been subsidized by the state. As the state reduces its subsidy, the portion of tuition that the students see nessasarily increases.

There is also a slight market distortion in that the state only subsidizes a portion of the market (public schools for in state students).