Those are the companies that were actually accepted to Y-Combinator. The Y-Combintor acceptance rate is said to be 3%. So, your odds of success are now more like 3% 7% = 0.2%*

All of this hinges on the assumption:

Y-combinator is a proxy for the start-up population.

Even taking the optimistic Y-Combinator outcome, would you be willing to accept a 7% chance of making $400K?

This is assuming you only get paid in that 1% equity while assuming the 40MM exit. If I got paid a SALARY I can accept + 1%, why wouldn't I take that chance? It is +EV. Compare this to the lottery, which carries a -EV.