* The media wants sensationalism, because sensationalism gets them peoples' attentions and thus money. There is nothing more sensational than riling up and pleading to peoples' emotions.
* The political powers that be want to keep the people divided. A divided people is easier to control and manipulate, whether it's smear campaigns during elections or undermining the safety mechanisms of our governmental institutions or straight up cancel culture.
How do we solve all this? Beats me, I'm in my mid 30s now and already tired of all this bullshit. I'll spend the rest of my days by myself in the countryside just enjoying the simplicities of life while y'all go and club each other silly.
I don't know if it's because of the two-party/first-past-the-post political system, or if that's a consequence as well, but everything about the US just oozes binary thinking (even on the international stage: remember Bush's "if you're not with us, you're against us" war rhetoric).
There's no room for nuance, everything must be black&white. The typical HN visitor should have the mental bandwidth for nuance, but more often than not that same mentality is showing even here.