I think part of what makes Trump so appealing to many Americans is that he is a powerful billionaire, but he's relatable in that he's not particularly hardworking or focused or brilliant or careful like most other powerful billionaires. Instead, he's what an average American (and the average respondant in this thread thus far) would be if you gave them a billion dollars and a bunch of power. Ignorant, obese, foul, and petty. His most ardent supporters will see nothing wrong with this because this is exactly the sort of pettiness that they direct toward their own enemies. But I think most adults who aren't trash, and who have responsibilities beyond themselves, can see how repulsive this is.
RIP McCain.