I really don't understand the view that it's OK to use downvoting to express disagreement. I think that what a downvote says, regardless of what's intended, is

I really don't understand the view that it's OK to use downvoting to express disagreement. I think that what a downvote says, regardless of what's intended, is "I do not want to see this type of post anymore." This makes sense if someone is misbehaving. I think it also makes sense for very extreme opinions. But for simple disagreement? Just because I disagree with you does not mean I want you to stop expressing your viewpoint.