Reading the ServerFault meta (very related to point 1 in that post) a common thread seems to be the decline of the "kindness" factor.
One of the more obvious indicator that bad questions are not welcome, is the down-voting. Yet most posts that received one do indeed deserve a down-vote. But often this is because people in general just suck at writing. Or suck at conveying their thoughts in a clear and concise manner.
Most of my posts are much too long for what I'm trying to say, and often not that clear. Yet after some edits (by other people at times) they can become much clearer. But at times this is too late. The question / answer might already be down-voted into oblivion (rightly so)...
Now if a person was notified of edits on a post they down-voted, they could review it, to see if their opinions have changed. Having a down-vote removed will make people feel like they are being heard. Or at the very least it will show that their question is still receiving attention from the community.
It's quite harsh to think that a bunch of people read your post, down-voted it and then never looked at it again. Dismissing you and your problems on a whim, in a place where you were reaching out and asking for help.