You can invest in Apple stock in the early 90s because you are a savvy investor who sees the massive potential, or you can invest in them because the stock shows up at the top of an alphabetical list. Either way you're rich, and get called a brilliant investor, while all the people who invested in ZZCO because they picked the bottom of the alphabetical list, or some other similarly random choice, are bankrupt.
Of course you can invest at random and it will sometimes work. But it does not explain the realities of the industry. Even just one of the top funds has an infinitesimally small chance of existing randomly, let alone a glut of them.
The impeccable track record of index funds suggests that "Even just one of the top funds has an infinitesimally small chance of existing randomly" is not actually correct.
Well index funds aren't 'the top funds', they're the benchmark against which the alpha of the top funds is measured. If we change the framing to over/underperforming the S&P500 I don't see how the argument changes. RenTec is up 66% per year since 1988, how could that possibly be random?