I think downvoting as a disagreement would be fine if (on HN) it did not cause a post to become grey or in worse case, leads to it getting flagged and then made

I think downvoting as a disagreement would be fine if (on HN) it did not cause a post to become grey or in worse case, leads to it getting flagged and then made invisible to everyone without showdead on. Due to these effects, downvotes are used as a tool of censorship. It's explicitly used that way in many cases, to make sure that unpopular opinions/ideas are not seen by more people. Because they do not believe people are capable of making judgements for themselves, and must be protected from unpopular speech, because if they accidentally see it, they might end up agreeing with it. We can't have that, can we?