The Scourge aims to remove negative, and largely unpredicted, phenomena that have emerged as Ethereum has grown in economic and geopolitical prominence: roadmap items here primarily attempt to rectify malicious MEV, network censorship, and staking pool centralization.
From a practical perspective, Ethereum has already separated block proposers and block builders.
However, this is facilitated by third parties and not necessarily permanent.
At this point, it makes little economic sense for
a block proposer (validator) to spend resources building a block, given they will ultimately receive much of the MEV from its ordering in any case. As such, proposing and building
have been effectively separated from an economic perspective (there are a few dozen builders that dominate the market). There is reason to enshrine this seperation at the protocol level, however, since it may not always be the case.
Moreover, if we enshrine PBS alongside Inclusion Lists, we can force the builders to include transactions that meet some threshold of gas and time.
By doing so, we can effectively prohibit censorship via block builders. It also opens the door for other MEV solutions, such as burning.