This is nearly always a problem in open communities with voting. Even if such ettiquette is in place, enough people will ignore it or disagree on what it means

This is nearly always a problem in open communities with voting. Even if such ettiquette is in place, enough people will ignore it or disagree on what it means that it may as well not exist. As a result, discussions boil down to relatively inoffensive and well-accepted opinions as those who disagree with the hivemind's consensus are either downvoted or are afraid of being downvoted because they know their contribution won't be accepted. The only online spaces I've seen where this isn't a problem are those that are strongly moderated, for example Reddit's /r/AskHistorians, and spaces where the community is small, tight-knit and known to each other. In the former case, the responsibility for determining what has any value and what doesn't is left to the moderators, who follow strict, publicly visible rules. Anything left is required to be high-quality. In the second, either people assume the best of each other or they're more averse to conflict. I like to believe the former.