I actually believe that this kind of minimalistic feedback is non-constructive, especially the negative reactions.
I brought this up in the other recent meta-discussion:
This subject was also touched on the talk “The Hard Parts of Open Source” by Evan Czaplicki (which was brought up in the popularity thread).
At 37:45, Evan claims that this type of feedback is a form of de-contextualization, which is helps making topics more viral; then at 38:38, he claims that this is a form of a powerful incentive for our interactions to go really poorly.
He further discusses this topic at 44:02, and explains how this kind of feedback is not contributing to the discussion, and worsening how people feel about their place in the community.