It's false that
no fund manager is consistently beating the market; you can easily find actively managed funds that have beaten the market for the last 5 years. The big debate is whether this is due to luck or skill, whether it's possible to tell the difference and whether it's possible to determine which fund manager will be successful in the future.
Uber is part of some indexes; S&P500 isn't the only one. The efficient markets hypothesis is obviously false, although from a distance it's usually a decent approximation.
And in case I'm about to get downvoted for violating the consensus -- 100% of my long-term investments are currently in index funds. But with the growing share of indexed investments, this is a very interesting question.
There are currently trillions of dollars (and growing) following the simple momentum strategy that index funds represent. It almost beggars belief that this is not, and will never, be exploited for gain.