Most of the staff here is opposed to ever having a dislike button. Given how people have abused the like button for spam in the past, there's no doubt they'd spam the dislike function. Having a dislike function also tends to make users wary of posting--what if their opinion is unpopular and they get a ton of dislikes for it? They might not want to comment because of it. As a forum, it's best to allow as much conversation as possible. If a comment is against the rules, it'll get deleted, and if a comment is wrong, I'm sure 50 people will step up with the correct information.