Donald Trump doesn’t epitomize the better angels of our anti-establishment desires (freedom and justice). The establishment is extremely disdainful of him, though. So, I reckon supporting him is good enough for a lot of people to make the point and poke the establishment in the eye with it.
It’s the same impulse, and I must say I somewhat share it, to shake show offs who police arbitrarily standard grammatical forms and pronunciation (i.e. forms with no logical basis for clarity, just conformity, snobbery, and status grubbing).
The whole farce does raise an interesting political question: at what point does policy matter less than integrity? It seems most people will vote for a corrupt politician aligned with their values over a principled politician with a different worldview. I think at some point you need to put policy aside and scrub a political ship when it has too many barnacles on it.