Actually, that's how comments and links are ranked on this very website. Moreover, still on this very website, not everyone can downvote, and the threshold is a

Actually, that's how comments and links are ranked on this very website. Moreover, still on this very website, not everyone can downvote, and the threshold is a quantitative measure of likes. So literally, you comment's font color is due to what you sarcastically suggest we do. Finally, i'm guilty of occasionally looking at some HN user profile and just to see how many upvotes it has. If the user has 15k+, I always go "wooooow" ^^ So yeah. But then again, as a fellow commenter has already pointed out, a like requires a click and a citation a publication.