I recently answered a question without providing specific sources. @MattDMo helpfully responded asking for me to update with sources, which seems appropriate, and I've added references. However, my answer received a negative vote as well, which seems strange as the answer is correct and there are no other answers on the question.
I certainly approve of the push for proper sourcing, and think that answers with sources should receive more credit than those without. I also approve of this idea to improve popular posts that have a lot of speculation or unsourced answers. But it seems to me that there's at least some space for an appeal to authority. The question I answered is about host-pathogen interactions, and I have a PhD in immunology and have taught several courses on precisely this topic.
It takes far more time to properly source an answer. This additional barrier, particularly on questions where I do not need to do any research to know the answer, makes me less likely to put in the effort. Again, I'm 100% on board with someone that does put in the effort to get more credit than me - I'm not saying that my authority should trump a good source. But I could use some of my own papers or course syllabi as a source for this question, so it seems silly that I should lose rep for answering it.