Or you could also say failing to expand the characters leaves them much closer to the way a person might be presented in a dream? I've never dreamt about someones backstory or even their motivation, they just are.
I agree the discussion would still be happening even if there was character development beyond Cobb, although at that point we might be much closer to an accepted answer vs a crackpot theory.
As I said, I had considered that but I just see it as a flaw in Nolan's writing. I'm not willing to let him off that easily is my point, basically, and there's enough evidence within the film to point otherwise.
I do think the film is probably Cobb dreaming, right enough, but even using the "it's a dream argument" still doesn't overcome some of the other flaws within the film.
I also thought it was a good film, but not his best.
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