I hate to say it, but absent the magical 'replicator technology' of Star Trek, then any galactic empire is going to have ships moving grain and other basic foodstuffs about. That concept is a core one in Dune, for instance, "Even our poor pundi rice from Caladan." Duke Leto tells Paul while emphasising the pervasiveness and importance of the galactic trading company CHOAM.

Nor should it be required that a text must always have some kind of point or comment to make about every incident or situation. One can write about rape without the entire story being about it. One can write about Empire without having the obligatory swipe at colonialism (BTW these two are not necessarily the same thing).

By the same token, characters need not be deep and with complex motivations. Nor do they need to change with time and experience. Lots of people are shallow and simple and go through life without really noticing anything, much less being changed by it! If it wasn't like that, nothing would ever get done!

As for the joy, the humour, the unfolding of something wondrous and unexpected. That's space opera, and clearly Snyder is not making space opera any more than he is making heroic fantasy "There are no heroes." as he points out.

That's why Snyders' cut of 'Justice League' was so much better than the original. Not shiny plastic heroes, just flawed people doing what they can and what they must, with the tools they have, often reluctantly and sometimes getting it wrong.

It sounds to me as if Rebel Moon is about people caught up in a shitty situation and being forced by circumstance to try and do something about it. Sort of like everyone in Europe between 1939 and 1945. In that sort of situation character development either doesn't happen or it's called PTSD.

That does not make Rebel Moon either a good film or a bad one. Just one that isn't about what you thought it should be about!