It is interesting just how much Y-Combinator itself resembles the business model of a university, except that it really can make a deal for a percent of a student's future earnings in a socially palatable way. Like a top university, much of its value seems to come from signaling and the hype generated just from the label of being a Y-Combinator startup.

This may or not be correlated with the actual advice but it is certainly correlated with the difficulty of the admission process, and this forms a positive feedback loop. Top universities also have on their side the fact that having rich parents very much correlates with future success, which in term helps perpetuate their prestige and ability to charge more for admissions.