Most people here keep extremism out here anyway. Emotional arguments don't succeed to gain traction, you have to be factual and nuanced to gain respect here, and as far as I see blind extremism doesn't get that far.
On Reddit the comparison used to be Digg. (I left three years ago, so I don't know what happened in the mean time.)
If you have something to say, say it. Reddit's probably irrelevant, and for the record, for any population, there's a lot of people smarter than you and me. Particularly if you and I are engaging in lazy categorization.
After all, this whole discussion is attached to a story about how a group of people took the time, because of their political motivations, to attempt to "attack" another group of people on a web site. Seems like pretty lame behavior to me.
I'm just as guilty as the next person of saying something rude on HN every now and then, but for the most part I and I suspect most others do our best to make substantive contributions to the discussions here.