MEV, or Maximum Extractable Value is, in layman's terms, "push your blockchain transaction forward" as a service provided by validators. By changing the ordering of transactions in a block, validators earn additional fees for putting one event in front of the others, as well as for including and excluding them.
A week ago one of the Ethereum validators used a specific software for his node to launch a transaction manipulation tactic that enabled him to replace several MEV transactions.
The result was that a solo node operator who had only registered 2 weeks before the event, gained 25.3 million USD. Other MEV bots who followed the gentleman’s agreement suffered, but the victims of this operation were the general public, meaning the Ethereum users.
In short, in PoS blockchains, MEV allows for-profit validators to earn more fees, thus increasing their ownership in the network compared to those validators who do not order transactions, and compared to simple token holders.
In Sybil-resistant blockchains, like Humanode, a validator is a person who has the same ownership of the blockchain as others, indifferent to the number of tokens staked. The fees are distributed equally based on the validator's uptime.
Imagine validators follow the same ordering to increase the fees from the users. In this situation, MEV is distributed equally among all the participants.
Anybody could get a share of an MEV-generated public good. A validator would not be able to increase his chance of ordering the transactions in a block, and it would be unreasonable/impossible for him to develop special software to only enrich himself.
Human nodes have the incentive to contribute to open source, collectively funded, and mutually agreed upon MEV protocols.
While it is great to find ways to get rid of MEV and give value back to the users, MEV exists on almost every layer of the ecosystem, from consensus, to protocol, to applications like decentralized exchanges. Even if we change the consensus to prevent incidents like what happened here, MEV bot developers will find a way to apply it on the application level.
After all, it is only natural for validators to embrace the opportunity.