Earlier quoted context omitted.
Essentially you're talking about roughly 33% or so of the American electorate, that's bound to get some downvotes, I wouldn't sweat it, note the good guys, upvote them where you can and stick around to stop it from sliding away even further. And yes, it is annoying. Also: typically it corrects itself in the longer run, so don't take a snapshot like this as the end state.
I've been here for almost 15 years and this is not some normal blip. It's true that the 2016 comment threads (the only corollary to this that I have seen) sucked, but they were not dominated by the toxic as this one is. It is not true that a third of the population is partaking in apologetics for violence. But it is true that more than half the community here appears to be. Thanks for your reply, though.
To your point though, this forum does occasionally flirt with violence. Over the summer, some were waxing poetic about how "riots are the language of the oppressed" and arguing that burning someone's business to the ground isn't violence but rather "just property damage". Some were arguing that antifa and other violent groups were "freedom fighters" and so on. So yes, it does get pretty toxic here, but this thread isn't it.