I think your fire analogy is off. An occasional conflagration in a highly-populated city doesn't do anything to promote the quality of the environment. Quite the opposite.
Since I made an explicit analogy to a forest, rewriting it to be about something else kind of makes my point for me.
When? I don't remember that, and I just searched the email archive and didn't find it. I found a mention of 8chan, but not with examples, and certainly not with links to people organizing to target threads here—which is hardly something we would be disagreeing about. Obviously that's abusive.
I can't find anything about HN at your third link. The others don't seem to contain much, but I'll take another look tomorrow.
(p.s. HN's software autokilled your comment for what I hope are obvious reasons.)
The lesson in this case is not that a generic flamewar about Trump belongs at the top of the #1 thread on HN. If the argument is that I shouldn't have moderated that, I disagree and am pretty sure the community would disagree.
Rather, the lesson in this case is that, because the topic was attracting attention because Trump, this was the worst possible moment for HN to be discussing ultraviolet blood irradiation. A curious discussion was not possible. Thus I downweighted the submission off the front page at the same time as I moderated that flamewar.
I think your fire analogy is off. A better one would be fires in a city, and those don't promote quality. Quite the opposite.