In the USA we're just predisposed to elect bad people, a significant segment of the voting public think electing a game show host is a good move, this sort of voting population will have effects at all levels.
Then you have the game mentality that you have to pick the candidate with the most chance of winning that still shares some of your views, or that the polling shows your higher pick will lose. Ranked choice could really help here.
By the time you get to the general election it's basically a choice between a shit sandwich and a shit sandwich without the bread.