[zeroclip]

In Ethereum's proof of stake model, validators do not control the rules and cannot force a change in the protocol. People choose to run nodes, these nodes may or may not be validator nodes, and this software is what enforces the protocol rules across the network. A majority of nodes would have to come to consensus on a change for it to be successful - this happened with DAO, EIP-1559, and probably soon the PoS merge.

It is free to run a node, and the market can freely decide to not support a chain. This is how you end up with ETC being relatively worthless even though there was a group of "rich plutocratic elites" that tried to make it succeed.

There are "influencers" like Vitalik, EF, several client teams, and thousands of hobbyists who work on research and development for the protocol, and these people do lead the direction of the technology moreso than the average user. But this is how all open source works: a small number of people make decisions, and a much larger group of people opt-in to those choices, becoming users. This is also how you end up with multiple blockchains: not everybody was happy using Bitcoin, so some people started to develop Ethereum instead.