While I've never seen The Walking Dead, I'm a little puzzled why someone would balk at a post-apocalyptic "nihilistic display of humanity where tribal survival is all that matters and every individual encountered is almost certainly some sort of rapist or cannibal and just needs to be stomped out". Without civilization and culture this is what human beings are like. It's the "state of nature" Hobbes wrote about, and much of it fits with observed behavior of hunter-gatherers as well as chimpanzees.

I'm not saying you and me and all the nice friendly people you know are like this, deep down. I mean, some of us probably are and are just good at hiding it, but many of us aren't. But in a Malthusian scenario where survival is at a premium and the material abundance of modern civilization is no longer here, who do you think is going to survive?