I agree with your overall point, but Wikipedia has a singular mission. Social settings can have wildy different missions from shitposting, to hobbies, study groups, to support groups, etc. There is no singular moderation ethos that can apply to all of them, that's why decentralization is important in social media.
We want to algorithms to work for the people, not have people slaving for the algorithms.
Absolutely I was not trying to take away from your point! Cory Doctorow actually recently wrote a good piece on Wikipedia that you reminded me of.