1) My over exaggerated snark from posts earlier was largely for comic effect, and in some ways self deprecating, because prior to late 2017, those were views I would have held myself. I would have unquestionably held sim and immersion as apex priorities in play, and derided any sort of hard encoded rules or system that didn't implicitly or explicitly encode that value set.
In my view at that time 6 years ago, I would have imagined, I would have told anyone who asked that narrative style games were by definition functionally "incoherent".
And the reason I felt that way was because of the notion I had about simulationism---that it was paramount to the overall RPG experience. Sure, it didn't matter that I kind of hated a lot of the baggage sim entailed---the need to "gate" content from players because that's what was "realistic". The need to ignore what were clear dramatic needs of the characters, based on their build and background, because sim doesn't countenance playing to the character. That's by default undoing the nature of sim, and undoing the nature of sim in play means you're likely "ruining" the opportunities for true, deep character immersion.
But I was definitely starting to question by late 2017. Based on my described experience with Savage Worlds, where after a year and a half I could no longer justify or rationalize decisions I was making as a GM based solely on "extrapolation" and "fictional causality".
And it bothered me, because I somehow felt I was being untrue to the paradigm I held dear.
But cognitive dissonance is an interesting thing. So when I tried Dungeon World in late 2017, and totally didn't get it, but saw glimpses of what it was trying to do, I had to admit that there must be something incomplete in my understanding of a GM's role when it came to sim.
The key thing I discovered---that the entire foundation of simulationism rests on---is that I had the notion that I was doing something with sim that simply wasn't the case.
Sure, I was extrapolating, and adhering to causality with all my might, but those processes were only heuristics to the bigger process of "Make s**t up." Or in the more formal vernacular, "Introduce fiction".
I had never examined the broader point of authorial authority --- that I was merely privileged in my ability to introduce fiction to play. The fact that I was using some heuristics---increasingly faulty heuristics beyond a certain length of play/gamestate---to introduce fiction didn't change the fact that what I was doing was introducing/authoring fiction, nothing less, nothing more.
I think the larger resistance of some GMs to narrative style gaming is resistance to this reality. It feels . . . less ennobling, somehow, if the GM role is reduced from "maintainer of game world fidelity" and "keeper of the secret tomes of history" and "grand master of the hidden backstory that shall amaze and astound upon reveal" to "Person with the most authority to make s**t up."
But as soon as I could accept that reality, it unlocked an entirely new realm of RPG play. I'd never have fallen in love with Ironsworn without that paradigm shift. And I can't imagine how much I would have missed out on if I hadn't.
2) Over time I was becoming increasingly disillusioned with how difficult it was to even get the thing that sim supposedly promised---deep immersion. There seemed to be so much sacrificed---character stakes, stronger dramatic tension, player investment in something beyond, "Okay, we're exploring some new cool place that's mostly like all the other cool places we've already explored, and meeting more NPCs we don't care about. When do we get to fight again?"
Not only wasn't sim producing the one thing I cared about---deep immersion---it wasn't even producing intermediate positives.
And I'm willing to bet there's a lot of GMs that have the same problem. Trad sim priorities, unless deeply invested by the players, is largely ineffective at producing more enjoyable intermediate drama/stakes the players really care about.