About people being stupid or racist to vote for Trump ... maybe, but there was a post I saw earlier today -- I'm not sure how to attribute it, I think it showed up on Tumblr first, but I think it explains pretty well how people can be racist and not evil ... not that racism is ok, but that they are literally unaware.
Basically, it's about how great it is that Ron Weasley is racist::
Ron Weasleys character is consciously written as somewhat racist. Not as racist as Malfoy, of course - he doesnt scoff at mudbloods and halfbloods, and he doesnt see himself as superior at all. Still, he unquestionably accepts the inferior position of house elves (they love serving), when he finds out that Lupins werewolf his reaction is not only scared but also disgusted (Dont touch me!) and he is clearly very uncomfortable finding out that Hagrid is half-giant (giants are wild and savage).
And this is brilliant. Because it demonstrates that racism isnt only present in clearly malicious and evil people, in the Malfoys and Blacks - its also there in warm, kind, funny people who just happened to learn some pretty toxic things growing up in a pretty toxic society. And they can unlearn them too, with some time and effort. Ron eventually accepts Hagrids parentage, lets Lupin bandage his leg and in the final battle, he worries about the safety of the house elves.
Some people are prejudiced because they are evil, and some people are prejudiced because they dont know better yet. And those people can learn better, and become better people. And thats an important lesson. The lesson taught about discrimination shouldnt be only evil people do it, because then all readers will assume it doesnt apply to them. Instead old JK teaches us you too are probably doing it, and you should do stop ASAP.