One half-cocked idea I can think of is downvotes require a comment explaining why. Conversationally, "I agree" or "that's correct" requires no follow on conversation. However, "I disagree" or "that's wrong" requires some sort of counter-argument or reason why you disagree. IMO, it does some good in making people explain their position, at least copy/paste another position, or shitpost and then they can deal with their own downvotes.