There's a series called The Bite, it was filmed during earlier quarantine times of the ongoing pandemic and features a bunch of cast from The Good Fight. Is good.
Half the population claims it's all a hoax and lets zombies bite them because anything else is a violation of their freedoms
Large swaths of gun owners take to the streets, and half of them die quickly because they put more money into the number of guns they had or making them tacticool instead of putting rounds through them or sighting them in.
It gets overly politicized.
The literal collapse of civilization, yet some corners of the government and billionaires are still trying to milk out the last drop of money
I actually think it would be good uniting force for a divided country:
The "it's a hoax" portion of the population will simply become zombies
The "we love guns" portion of the population can now take their life frustrations out on the zombies
The "we need to fix this world" portion of the population will learn to fight too and provide vital aid and supplies to the (likely growing) "we love guns" group
The "we need run away from this madness" portion of the population will just hunker down and play on their smartphones
I think you're a little off on the "we need to fix this world" guys.
Although zombie films / TV series lean heavily into the action side of things, that's just because it's more entertaining than watching people building things, developing tech, doing scientific research.
Remember with COVID 19? Huge numbers of people immediately set out to find a cure, inventing and deploying ways to prevent and monitor the spread, creating pop-in treatment centres, etc.
Feed, by Mira Grant, is fun because it takes place years after a zombie uprising, but in a world where George Romero movies existed, so everyone knew what to do. It was a catastrophe, but not an apocalypse.
Avenue 5 has a pretty funny scene where a series of skeptical conspiracy theorist types are ignoring a very specific warning, claiming that the people they see dying before their very eyes are an illusion some kind of special effects and each follows to their own death.