Walking Dead is a TV show that makes zero sense whatsoever. I dropped watching it after 2.5 seasons, because after season 1 it lost any semblance of a plot, and became a TV-show-equivalent of the very zombies it portrays - mindlessly wandering around. I can't understand why it is so popular.
I agree that it's long overstayed its welcome, but from what I gather, the zombies are mostly irrelevant. You could swap out "zombie outbreak" with any other persistent hazard that causes the breakdown of civilization and provides a constant background threat to the actual focus of the story: the people who have to survive and deal with each other/the environment they're faced with after said breakdown.
As much as I enjoyed the early seasons, I understand that it was always the goal of the original author and the showrunners to make it more about people being people in extreme circumstances. If it was decades earlier it could just as easily have gone the Fallout route and used nuclear war/radioactive hazards/mutants/etc. as the backdrop and the stories could have stayed 95% the same.
IIRC the creator (Frank Darabont?) left after the first season, and the show has suffered tremendously since. The only reason for it's success is perhaps the love people had for zombies.
I watched a few of season 2's episodes, but gave up pretty quickly.
