I honestly think that the video gaming community has the right to bomb a review, especially when the developer refuses to listen to its community, for example GTA V removed the ability to use mods which is the main reason people played the game in the first place and their steam reviews tanked reason being that the Devs took away the gameplay feature that mattered to the player base the most.
I have seen allot of stupid things happen to steam in my five years on the platform and this is not the worst, but it is pretty shady. They are trying to remove the right to protest a game by adding this "Review Chart".
If valve is so afraid of Game Developers pulling out of steam because of the review system, then they need to remove it otherwise i say let them leave.