Functionally equivalent (I will accept looser implementations) of a "down vote", or something to show disagreement with a comment.
@firstuserhere Well the most recent one is YouTube, but I distinctly remember thinking "here we go again" when it happened, though don't remember what example I had in mind.
@colorednoise The youtube one is what comes to my mind as well, but the reasons for removal are very different there. Youtube has 3 different groups to please - the users, the creators, and the advertisors. By removing the downvote, they made a decision that was useful for advertisors but not so much for the users and creators.
Manifold is not in a position like that yet. There are only 2 sorts for comments : newest and the most liked. However, the comments with the most likes is not always the most important one (meme comments get tons of likes, for example). Manifold currently does have a comment section which is where most of the discussion about a market is supposed to happen, but does not have good quality tools to surface high-quality comments yet.
@firstuserhere Just curious, why does it help advertisers for the downvote to be removed?