Every platform with votes does that. Including HN. A community's feeling is largely determined by its sorting algorithm, and voting selects for engagement/ragebait. Chronological is more balanced, but you have to prevent spam because it also doesn't punish spam. You could make it difficult to get an account, but we're all used to moderators abusing the power now, so that leads to self censorship. You could retry the Something Awful way where you let people have unlimited accounts but they have to pay $10 each time, heh.

The other main way would be manual curation. That basically makes a non-interactive website.