(This post rescues content from a Facebook comment I got carried away with recently.)
There's so much to write about the Expanse. It's such a relief to find a science fiction show with an ambitiously futuristic setting depicted in a way that doesn't make scientifically literate people cringe and shout at the television.
Also, it shines at taking the time for quiet moments of character work, from Miller's lonely, poignant realization in s01 that he wasn't the talented office maverick, just incompetent and unreliable, right up to the quiet, unseen payoff of Naomi's years-long efforts to save her son from his father's influence, in the final seconds of s06.
On many axes, it's the best SF on television, which is saying something, as there are so many competitors. Science fiction output is following some sort of Moore's law of endless expansion, in response to society's need for mythic stories of relevance to modern life, itself a symptom of the meaning crisis of modern society. But this is a mixed blessing, because the resulting shows & movies are often drawn to using the superficial trappings of science fiction, spaceships and lasers (pew pew!), while failing to fulfil the deeper psychological needs of mythical or symbolic significance that brought about their creation. The Expanse is perhaps the prime example of this.
My fantastic SF podcast guy defines SF as the arena in which we forge new myths of psychological meaning for modern life, which are sorely needed as traditional myths dwindle in relevance, as they are predominantly based on nature and superstition. Movements such as spiritual atheism are a reflection that even the least spiritual amongst us recognize that something is missing.
I do concede that defining SF in this way is a bit of a cheat. It's somewhat aggrandizing, claiming any great mythic work as actually being part of the SF genre, an no doubt is a somewhat defensive reaction to mainstream dismissal of science fiction as puerile. But it does provide a marvellous framework for discussion, and adopting this definition makes several previously puzzling things fall into place.
It settles the revealing, never-ending debates over which works are, and are not, science fiction. Somewhat tellingly, to me, such debates are irreconcilable precisely because of the misnomer "science fiction", which was never really about the science to begin with, as this style of fiction has existed long before science was the focus. It only gravitated towards using science as it became apparent that is now where society's power and transformation springs from - our incarnation of gods and magic - and the name "science fiction" was then applied post-facto, missing the underlying fact that this is just mythic fiction with some modern attributes.
This definition perfectly explains things like how the first half of the movie "Sunshine" could be such astonishing science-fiction, while the second half - set aboard the exact same spaceship - is just a mediocre slasher flick.
So. SF is the arena within which we construct new mythic narratives.
By this I mean that great science fiction tends to create a story that resonates because it leans on powerful mythic tropes - symbolic representations of psychological significance, character arcs mirroring Jungian archetypes, thematic elements that are told allegorically, suggesting things to the reader/watcher on a level that can be more powerful than merely stating them directly to the conscious mind.
In this way, all-time-great examples such as 2001: A Space Odyssey (the title being conscious of this mythic entanglement) leans heavily into themes such as humanity watched over by an ancient, mysterious, godlike alien influence which has literally created humanity in its present form, and observes as we now reach a second inflection point, materializing not just a tale of personal transcendence (although it is certainly that), but one of species-wide sublimation - suggesting that it is time for us all to reach spiritual adulthood, to graduate to whatever comes next, to meet and be transformed by the wise and powerful force that has shepherded humanity through our previous prehistorical transitions.
I could go on with similar examples, but will just briefly mention the original Matrix movie, which is a story which resonates because it is absolutely soaked in allegory of both religious transcendence and Jungian archetypes - which are so on-the-nose that it cannot possibly be accidental, a fact acknowledged directly by the creators in the sequels, when they depict the Architect, ultimate villain encountered at the narrative peak of the story, as a prim, middle aged, white bearded gentleman, wearing an Edwardian suit. He speaks in a precise, almost Germanic manner. This is, unmistakably, Sigmund Freud. Why is Freud the villain of the Matrix? Because Freud was a contemporaneous antagonist to Jung, resisting Jung's ideas of self actualization through reconciliation of the archetypes, just as the Architect resists Neo's progression along that same path.
It may be my own lack of imagination, but compared to examples like this, the Expanse starts to look a bit thin. I don't see any symbolism or allegory. There is some good character work but no actual arcs of transcendence. Through the unfortunate realities of converting books to screen, large chunks of what could have been the most meaningful story were simply abandoned and will apparently never be finished on the screen. In their stead, what would have been mythic elements become a series of "McGuffin of the week", as we never circle back to resolve why the protomolecule was created, why it was sent to our ancient solar system, why it turns people into nuclear-powered zombies, and what force destroyed the protomolecule creators, and why? And that's just series one's unresolved elements.
So, lacking that, what the Expanse has to offer is its superlative world-building and sane, believable depictions of a gritty interplanetary future. Which is no small feat - arguably nobody else has done it better. But, for me, it isn't enough. Maybe that's just because I'm a godless heathen who looks to get my spiritual fix through TV shows about spaceships. Or maybe it's because science fiction is where we show ourselves what we're capable of, what to aim for, and I believe we can aim higher than just exciting technological dystopias.