I should mention I've never read the manga, I've only watched the Netflix movie. And while I think it's a great post-apocalyptic scifi movie, I thought BLAME! was considered cyberpunk?

The movie is about a distant future where self-replicating machines have covered the entire planet in a giant City (although calling it a "city" is a bit generous, it's mostly a series of pipes and corridors). In this future, the machines now detect all humans as intruders and are trying to eradicate them. So the last remaining humans are just trying to find a way to eke out an existence.

Am I missing something? Can someone explain why this is usually included in lists of cyberpunk anime? It all feels very post-apocalyptic to me. Is it just the lack of plants/nature that gives it a cyberpunk label? Or is there something from the manga that wasn't brought over into the movie and would've added some cyberpunk themes?

To be clear, I'm not saying this is a bad movie by any means, I'm just confused how it's considered cyberpunk. Here's a trailer, and it's still available on Netflix.