I think it should be required that when a person downvotes a post or comment, they should need to supply a comment as to why. That would have multiple benefits. One, it is maddening to make a comment in earnest and get downvoted but no feedback why it was downvoted. Two, it would reduce the number of people who downvote a comment simply because they disagree as they would have to expose their own opinion and risk the…
Something that I've learned: nobody owes you an explanation for why they disagree with you, nor are they bound to care whether you learn something. Furthermore, I would argue that self-reflection about why people might disagree with your viewpoints is a valuable experience in that it provides an opportunity to practice empathy and awareness in how your words are perceived by others.
It's easier to practice empathy when you're not blindly guessing at what bothered the downvoter.