In asymmetric high risk/reward environments, what YC does is not unusual. When a trade has 99% of failing but 1% will pay for all the bets and
then some, you simply cannot take large positional bets that results in equal power dynamics.
They've built something heavily coveted and exclusive that people participating cannot see that they are gambling with their time and life.
It's very comforting to founders to feel safety in numbers when operating in an illiquid market (the goal is to sell your shares to a buyer whether its secondary market or IPO) but know this:
Illiquid markets are rife with manipulation and false positives.