Do people really comment this? I've never seen anyone comment anything along the lines of "you don't need to provide a reason to downvote" on a question they are downvoting. I would probably call them out and/or flag a mod if I saw it. Is this a very recent thing?
That being said, I agree that Stack Overflow has a duplicate issue.
Re:Looking for a new CEO
by albertzeyer on Thursday March 28, 2019 @05:58PM
(#19517040)
Yes, I have seen that a few times. E.g. some own question:
https://stackoverflow.com/questions/9945648/
Or another one, which recovered now: https://stackoverflow.com/questions/9946322 (Initially votes were all negative, but over time more and more positive votes came.)
The other issue is, even when the reason is given, sometimes you would not agree with that. E.g. sometimes people claim it's a duplicate, although they are not deep enough into the topic to really tell, and then the question gets closed. Or people claim is subjective, while in fact objective answers are possible. Or many other things.