I think I’ve settled on the latter. Disagreement is maybe best communicated by the absence of an upvote? And downvotes work best when they signal something that is just off base, and while not reportable, is not appreciated at a broad cultural level.
Downvote = “I think this should be less visible than it is.”
Generally for disagreeing with something that’s pretty petty.
But if it’s verifiably misinformation, downvotes are more than warranted.