If I am not mistaken, the following two assertions hold true for Ethereum PoS:
- An entity becomes a validator in the upcoming PoS block validation scheme by first issuing a special transaction to lock its stake.
- The rate of profit of a block validator in PoS scheme is proportional to its percentage share of the total stake being locked for block validation.
If my #2 assertion is correct then we can readily deduce that an entry of a new validator in the network decreases the rate of profit of all existing validators. This is obvious because for all existing validators, the percentage share of total validation stake decreases.
Now, if the above derivation is accurate then we find that it is rational for all existing validators to discourage a newcomer from entering the blockchain network's validators group.
Then if the mechanism for being a validator is indeed what I stated in my #1 assertion then the rational validators can censor a newcomer by refusing to validate the transaction that locks the stake. Since all of them will refuse that particular validation task, the transaction will never be mined into a block.
Then Ethereum PoS does have a censorship problem regarding the validator set. Right?
Note that one cannot say that the existing validators acted dishonestly by refusing to validate the stake-locking transaction. They only acted rational and the protocol for network entry led them to the sole profit maximizing action.
