I'm involved in several hybrid online and in-person communities, and two of them have had unpleasant incidents in the last couple of weeks. In one, a poorly-phrased but probably sincere question provoked a harsher-than-necessary response, which in turn provoked foul language, which in turn—but you can probably guess what happened next. In the other, a poor choice of words by someone whose intentions were clearly good provoked an unforgiving backlash, which in turn resulted in the speaker quitting the community.
I believe everyone involved was acting sincerely (i.e., not trolling). What separates the two cases in my mind is the same thing that separates accidents from recklessness. It's the difference between knocking a glass over because you were distracted and doing it because gosh, there's this party trick I want to show you and whoops, did I make a mess again? If one person told me "you screwed up," I might argue with them; if half a dozen told me, then I (hope that I) would accept that I'd done wrong and try to make amends. If I don't, that's on me, but if they keep telling me off once I've acknowledged my mistake, I reserve the right to believe that they're not actually trying to make the world a better place, but are instead trying to prove their zealotry. And that I feel justified in ignoring...
You can be completely right, and you still are going to have to engage folks who disagree with you. If you think that the only way forward is to be as uncompromising as possible, you will feel good about yourself, you will enjoy a certain moral purity, but you're not going to get what you want. And if you don't get what you want long enough, you will eventually think the whole system is rigged. And that will lead to more cynicism, and less participation, and a downward spiral of more injustice and more anger and more despair. And that's never been the source of our progress. That's how we cheat ourselves of progress.
— Barack Obama