Why would you downvote something? 'You weren't invited, just move along', exists.
Happy to say, I only ever upvote.
These posts typically have a top reply comment correcting the parent.
The downs help people reduce or avoid being influenced by even glancing at information that is no good.
Fortunately I don’t see many comments that are so wrong that I can say they are in fact false, but it does happen. In those cases, I think a downvote is valuable.
Sometimes people are mean about React and they must be punished.