On a few occasions, I have quit interesting arguments with people I respect, because it was in public Facebook comments and I could feel (and see, via reactions

On a few occasions, I have quit interesting arguments with people I respect, because it was in public Facebook comments and I could feel (and see, via reactions) the baying crowds forming camps on either side. And sure, hypothetically it could go to PMs, but these weren't close friends. "Gladiatorial" is exactly the kind of feeling I get from it. I don't think messageboards used to be this way before the proliferation of 'share' buttons and engagement-tracking algorithms. In the old days, people had to choose based on the thread title whether they wanted to read it. Today, Facebook notifies you: Trevor and Dan are going at it again.