I guess I should give it a watch one day. Even though - when reading your review - I couldn't help thinking of Snowpiercer myself. A film that I didn't particularly like.
By the way, I like how you make use of the 'final nail to the coffin' expression. Usually you would hope that loads of mediocre or bad movies would be the reason for a (movie) hype to pass but the mainstream crowd is like a horde of zombies that flocks to every sequel, remake, spin-off and so on to get their brains eaten.
Anyway, I was making a kind of zombie movie until a month ago and have to admit that describing it as a zombie movie - when telling other people about the story - left a bad taste in my mouth. Probably because there are too many zombie movies/ series already.
Anyway, interesting read and nice review. I will give it a watch as soon as it appears somewhere where I can legally see it. No rush though, as I am a little zombie saturated myself.
I think the zombie genre is one that is, and always has been, difficult to approach.
Romero's films even suffered from not really knowing what they want to be in terms of horror, silliness, and telling a much broader story.
I think, as with many genres, it is time for the zombie one to die, and eventually be revived with new approaches and more enthusiastic productions.