As the polls seem to indicate, it's not necessarily that people are switching to Trump, they're just abandoning Biden. Anyone who goes the Trump route is a dipshit and an asshole. It's that people, especially young people, do not want an octogenarian president who's currently supporting what is looking like a genocide, who isn't doing anything to help them afford to pay their bills (the stock market be damned), and whose future looks very bleak on nearly every measure. I'm not saying it's rational to sit out and let Trump win, but most people, and certainly the American electorate, are not rational voters. Freud's theory of the pleasure principle and the death drive are really apt here just as they were prior to WWII. When pleasure becomes decreasingly unobtainable and life becomes about "unpleasure" people start to unconsciously crave a state in which there is neither. Death. Death has no pleasure and no pain, so people begin to take reckless actions or to further the cause of violence because they don't have good enough reasons not to. It might not be rational, but it happens.