I don't disagree with any of your points, hell, I agree with all of them!

My point, I'll exemplify by Kojima here, is you don't work yourself into a character like (also named) Big Boss, Die Hardman, The Sorrow or whatever. You start there and work yourself backwards to make it somewhat believeable, considered.

And I feel like the same thing applies to Fury Road. You start off with a sick ass character like Immortan Joe and then figure out how the world works around him as a central figure. I mean you could take any of the aforementioned, give them like 0 explanation and consideration and they'd still be good. Big Boss the supersoldier is cool on it's own. Die Hardman President of the Post-Apocalypse US is a fucking baller concept. Immortan Joe the monster truck driving manbeast? Needs no further work, to work.

But they did and that's what elevates them as pieces of media. Immortan Joe isn't just a sick ass villain with no explanation, he's a sick-ass believable villain.

because George and his comrades manage to put a concrete, fleshed out world and a well considered, grounded plot in to a two hour long gonzo action chase scene.

Cause that's when you get this, and I'd argue Kojimas works also do this. You take MGS or Fury Road and strip all the world building out of it, you're left with Hardcore Henry, which I'd argue is still a very good movie in the sense of it accomplishes exactly and near-perfectly what it sets out to do, but it's just a 2 hour action romp.