I think one big thing here: where does fiction come from? what is a valid source of fiction in a roleplaying game and why? Does the fiction overriding the GM imply that there is some platonic ideal of what the narrative ought to look like, which needs to be course corrected if the mechanics and roleplaying don't emergently produce that narrative? Is it the players idea of what that story looks like, or is it the GMs? If it's the GMs then isn't the GM doing the overriding anyway?
Personally, I'm of the viewpoint that plot is a red herring, the game is a narratively rich space wherein one experiences "play" rather than a structured stroy that makes demands of its participants, and whatever actually happens should be accepted as the fiction. I think that the world of that fiction might change from the GM's notes as they adjust their own notes during and between sessions, whether because they think an element would be fun to introduce or whatever-- sometimes (though not all the time) a player thinking there might be a secret door somewhere might be something the GM internally says "Good Idea" to and rolls with it.
But you can't do it too often or too transparently because it changes the way the players experience the story in the same way that a writer doesn't experience a story the same way their reader does, like, you can and that's a perfectly acceptable way to play SOMETHING, but you give things up to get there. I see the notion of a fiction that makes demands as a sacred cow in terms of how a roleplaying game is usually played, where authorial control disrupts the fun. But obviously, you can have a storytelling game that is more about direct authorship of a narrative in a collaborative way and that can be fun too.
Because you can have both of these things, you can further have fun things that are on spectrums between them or combine them in some way, and that's where a lot of the experimentation in the medium tends to come from right now-- controlled authorship partially applied to that emergent space.
