I think we both speak of the same thing, but I come from dramaturgy background. Story is story, no matter the genre or medium. At its core, story is always about change in the character through dramatic arc. If there is none, it's journalism, for lack of better words. Mechanics are vastly different through media. For example, in screenplays you get to write only what you hear and what you see. Essay form is allowed only to explain to the creators of ultimate form what you mean.

When you shed all the layers of genres, when you come down to the basic principles of dramaturgy, you're left with the core of storytelling that's in all stories ever told. From Plato's Cave to Aristotelian unities onwards to Star Wars and Seinfeld, there are certain core principles which hold true in form and structure. Form, not formula. In dramatic arc and story structure there are elements which morph and trade places and these, along with psychological and visual motifs make a genre. It's probably valid approach to view/interpret this on a whole other level, and that's the beauty of it. This is just my viewpoint based on some experience and background in dramaturgy. It's a view on abstract principles of storytelling where you get to manipulate form and structure itself before you materialise it into particularities. Kind of like virtual functions, or better yet a class diagram of a story before you write it down. Dramatic theory is not competing with literary theory - it complements it, specializes it. I took dramatic theory as a heavy weapon which I find extremely useful in my work, but I didn't dwell much further into literary theory. I took some bits and pieces that I find useful for my work, like intertextuality (esp. biblical - which is tropey as it gets, Star Wars for example and Hero's Journey, but most modern literature as well)... etc. I have colleagues which are far more well-versed in literature theory than I am for when I need insight. I'm more concerned with dramatic mechanics and structure, because that's what I do and what interests me.

What I'm saying is that behind all of the layers of a genre, there is a common subset to all stories. If you start with that and build towards a genre, you get to see the specifics of how it modulates that core structure. SF, in that regard, is always heavily biased towards internal-driven change with accentuated wants and needs switch[1] where character is in an extreme psychological situation driven by an extreme physical situation flared by science. Character is driven into a corner where he/she has to act on his core flaw in order to achieve the need in order to change. Whereas fantasy has a character on a journey both physical and psychological through which he/she overcomes the flaw in his character in order to act on it when third act kicks in.

It's a bit of an abstract way of thinking, but I don't know how else to put it without first explaining all of the intro to dramatic theory, hah.

[1] Wants vs needs is the epitome of character arc mechanics. There's something character wants that drives his story arc, only to be exposed to his actual needs (what he really wants). Shedding his wants and fulfilling that need he discovered he overcomes his major flaw and thus changes his character.

Now, if you view through prism of that mechanics (core one though) and go back to genre structures you can clearly see where most differ (not all, there are blurry ones!). For example, if you look at Star Wars or Conan which are fantasy (one with SF theme and one with fantasy theme) - there's a clear flaw in the character that gets replaced by a need and fulfilled on the journey (actual one). Be it Force training vs Dagobah cave or Sword training vs Valeria. It's an actual quest! Now look at a clear-cut SF, for example Inconstant Moon episode from Outer Limits (check that out if you haven't!) or any of the more fabled STNG or DS9 episodes. In Inconstant Moon, main character realises this might be the final night of his (and everyone's life - Sun has gone Nova on the other side of the Earth (it's nighttime), and he notices Moon is exceptionally bright because of it... so he calls up his ex girlfriend (wants) and he becomes more open and free (needs).. or in DS9 Pale Moonlight (Moon, again!) where cptn. Sisko wants an action attack plan or whatever only to need to become vile and dirty character in order to win, thus overcoming his flaw (being a good guy)... no quest. When we return to Dune, that's where lines get blurred and there's an endless debate.

I mean, I could go on forever and we all could probably be right to most extents. This is just my way of thinking. Flair on top of all of that is of least concern, but is the most visible in a genre. By that I mean spaceships vs swords or whatever. It's just a motif. Hence why people commonly confuse Star Wars as an SF - which it isn't at all. Also a reason why new Star Trek movies aren't really SF. It's a fantasy or in ST case action story with an SF theme on top.

I'm really passionate about this subject (storytelling) and we have debates like these almost on a daily basis because we all love it. We all agree on one thing and that's that everything lies in character development and arc and grows from there, so excuse my elaborate intro to debating the topic!