Decentralization requires consensus mechanisms, and consensus mechanisms mixed with social media require some way to signal disapproval.

Downvotes are an extremely important part of establishing consensus about rewards. It is not possible to deal with plagiarism and spam without downvotes. It wouldn't even be possible to police tags, and every tag would be flooded with pornography (because all it takes is one upvote to make it worth tag flooding botnet spam pornography if there are no downvotes).

Normal social networks have entire departments and advanced algorithms keeping their networks free of spam, plagiarism, and pornography, and it still pops up. All we have is the downvote. Much hated, rarely used except by committed abuse fighters, but 100% mission critical.

Thank god that our witnesses actually understand the importance of downvotes!!

Any witness that publicly supports removal of downvotes from consensus algorithm loses my vote the second I become aware of it.