I mean he's not a leftist. I'm ignoring the constant sexual harassment and latent homophobia that seems to permeate the entire show and pretty much every character here and also that he's like a huge dick, but all his criticisms of people, the system and the world are oddly leftist. Never really noticed when I watched it back in it's heyday.
Out of all shows I've rewatched, I'd say King of the Hill holds up the best in this regard. There are a few episodes where you think it will go all 90s homophobic but pulls the rug out from under you.
A perfect example
I've recently been rewatching King of the Hill and have been really pleasantly surprised how well it holds up. Good guy Mike Judge.
Even the "bad opinions" the show displays in certain episodes are presented as such. There are a couple of lines here and there that could be accused of transphobia, but I feel like the show doesn't punch down, it just shows that Hank (or whoever) is just a bit behind the times