Sure, but it also says:
If you want to argue narrative structure, "setting DNA", then I would counter that the entire point of 40k is to present a dystopia on steroids, where absolutely everything sucks, there are no good sides and there aren't even helpful sides. Yes, Chaos, Necrons, Tyranids, Dark Eldars and Orcs are all much worse than the Imperium - but the Imperium isn't really helping against them. As I see it, part of the overarching dystopia is that humanity is preyed on by all sides, and in addition its own state is a North Korea on steroids in space which only makes everything even worse. The Imperium is not a necessity. The Imperium is not hard men making hard decisions. The Imperium is only just adding to the dystopia.
So, that is how I see the "setting DNA". Of course, that is an out-of-universe consideration - a different consideration from an in-universe one.
Plus, staying on the narrative level, well, defiance to me sounds like the most straight up satisfying option. We will win, or we will gloriously die in a righteous fight.
This was a while back, but it's a kind of a fundamental point so I'll return to it.
Suppose you are stranded in the middle of a boat in a stormy ocean, inside a leaky old boat which is slowly filling with water. It was a solid boat once, maybe, but now it has rotting wooden planks, and is stabbing you in the back with rusty nails.
That's the Imperium. This does not mean that, if you took the boat away,
you would be dry.
Likewise, you cannot say in good faith that if you simply took the Imperium away, humanity would be safe. It is simply absurd to suggest that when literally every depiction of the universe shows threats that are only
barely held in check as things stand. The fact that the space the Imperium occupies stops the existence of other, theoretical, much better organisations which could do the same job doesn't mean that if it collapsed tomorrow, things would be fine. Which is what we're actually discussing.
And
that's the tragedy of the Imperium. It is dysfunctional. It often makes things worse around it simply by being there. It is unequal. It is slowly failing. It is
terrible, in the Biblical sense. But it is also the
only thing protecting the bulk of humanity, and
this is a fundamental part of its tragedy, because it prevents an easy way out for the setting. If you could simply blow up the Imperium and everything would be fixed like the end of Return of the Jedi, the horror of 40k as a setting, and the moving heroism of people trying to hold back the encroaching darkness a little longer, would be vastly reduced.
This discussion has literally given me a headache so I'm going to take a minute to stand up and go and have a Lemsip and make supper.