Fair enough. Here is my take on why a person might vote for trump (aside from bigotry, hatred of trans people, etc): I think some people consider a Trump vote a protest vote. The condition of many black people in America has been bad under both democrats and republicans (though for the last several decades, republicans have been demonstrably worse). Institutional racism is real, and people are angry about the status quo. I think many people feel like both democrats and establishment republicans have failed them, and voting for an outsider might be a way to shake up the system. However, as a protest vote, Trump is a poor choice. He is the apotheosis of white privilege. He was born rich. His family business was notorious for discriminating against black people (both under DJT and his father). His own family members have warned the public that Trump is racist towards black people. His comments and actions during his first term are not consistent with a leader who wants to help people of colour. Trump is definitely shaking things up, but it won't be in a way that benefits anyone but straight white Christians of means.

I agree that alienating and dehumanizing voters can be counterproductive in a democracy. If democrats want to win next time, they have to persuade some portion of non-voting and republican-voting Americans to vote democrat instead. There are many methods of persuasion, though - and not all people are amenable to all forms of persuasion. No one likes to feel foolish, and surely some people who voted for Trump are feeling a bit foolish right now. Pointing out ironic examples like this guy who supported Trump and is gradually learning to regret his decision might have some merit.