People deleting questions after they have been answered is one of the reasons I stopped contributing. It's so energy draining to take the time and explain something to somebody and do it in a way that others with the same problem can understand & apply it as well only for them to delete the question for some reason.

I prefer not to delete, especially to an official answer, but it’s hard to let the obnoxious comments stand at the same time.

You can now report comments for being rude/unfriendly/unkind/condescending.

You and the reply below have BOTH deleted questions from SO because of social overhead. That's a surprising outcome that's never occurred to me. I can imagine that many interesting questions have disappeared this way.

I have noticed answers in comments a lot too. It seems like some aspect of the gamification. One theory is that people don't want to put any straightforward answers in actual answers because they seem anything straightforward to be unworthy of an actual answer.

I have my own standards for what makes a proper answer, and if I'm too confused or rushed to meet those standards I'll just leave a comment instead.

I've been yelled at for doing that on Stack Exchange sites other than SO.