The fact that this thread (https://news.ycombinator.com/item?id=33674562) survived for as long as it did despite wildly transphobic "automatic responses" (nitwit005's words, well put) tells me that we're probably on that downhill trend. I remember (vaguely) a particular automatic control existing to mitigate low-quality discussion by simply demoting threads with heavy flag/unflag trends from the front page, and here we have an example of a thread linking to a pretty inflammatory blog post that managed to stay on the front page for hours despite being littered with comments that were flagged/unflagged repeatedly. Even now it's #50, seven hours later.

Just with that single case study of a topic, yeah there's a downhill trend to be noted.

Edit: oh hey, the flagging actually worked this time. lol