In theory, for the system to be controlled by the elite - I guess we first have to define the elite. Let's say that's the top 0.001% - or the richest ~70k people on the planet.
1) That's still A LOT of people.
2) There's no way they're all going to collude together.
3) They don't (yet) have >50% of the world's wealth.
What am I missing?
Even in something more difficult to collude/setup like BTC, 4 pools could execute a 51% attack. As of Q2 2020, 65.08% of hash power was in China.
It doesn't take many people, especially because you need both money and a desire to be in Ethereum. As another example, 2241 individual wallets hold 42% of all BTC, while 35,604,096 wallets hold 1.24% of BTC - I would expect concentration to happen even more quickly in PoS.
Also, ETH has already forked over a doctrinal issue - I don't doubt it could happen again, but the PoS leaders will just directly double down.
This isn't a PoS/PoW argument - more that most public blockchains are inherently winner take all systems.