The main reason this EIP was pitched was to mitigate bid bots.
Except it incentives bid-bots by making it financially necessary to make it to linear rewards.
How many top 20 witnesses are running a bid bot? If the EIP threatened their bottom line they would veto the hardfork, which is exactly why it obviously benefits them.
RE: Steemit Update: HF21 Testnet, SPS, EIP, Rewards API, SMTs!