First, my second quoted bit isn't about wanting complete autonomy (as I understand that term). It's about wanting opposition in the fiction to feel as though it's in the fiction. The GM applying a rule to cause my character to do something doesn't feel as though it's coming from the fiction.
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How is having a decision imposed on you from outside the fiction immersive? It's not arising naturally from the fiction or the GM wouldn't need to Compel you to put it there. The GM is putting it there because they want to shape the scene or the story that way.
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I have seen--and played--characters who would do essentially what you have at the end of this paragraph, in games like D&D or COC or Savage Worlds (which IIRC also doesn't have the kinds of metagame incentives you're talking about here). I personally don't see those mechanics as helpful to roleplay, or necessary.
I agree that it is possible to be motivated--possibly even compelled--by forces inside and outside the character, and that that motivation or compulsion isn't strictly a matter of choice.
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I don't think I believe that in order to project oneself into a character, to understand that character, to behave in-fiction as they would, it's necessary to have those compulsions applied from outside the game. Any writer of fiction who has been surprised by the behavior of a character whose story he was writing seems likely to understand my point of view, here: I've recently been surprised by the decisions of at least one character I was playing, who ended up behaving in arguably suboptimal ways that made some sense looking back.
Even if compulsion from outside the fiction was a good way to model the forces you're talking about, I'm not sure it would make for good game play, and it might not make for verisimilitude
There's stuff in here that, it seems to me, would benefit from unpacking.
(1) Why is a compel not arising naturally from the fiction? The examples I'm familiar with from the rulebook seem to. For instance, p 14 of Fate Core has Landon's player accepting a compel on the aspect The Manners of a Goat, so that when he dances with a refined guest at the ball, he offends her. This seems very close to a CHA check in 5e D&D to determine the NPC's reaction, except instead of rolling a die and applying a CHA mod, the player elects to auto-fail and takes a Fate point. The example goes on to say that "Amanda [the GM] and Lenny [the player] play a bit to figure out how Landon puts his foot in his mouth". Now I think there's room in both the Fate and the D&D example to talk about when the best time is to invoke the mechanics - when the PC or NPC meet, or somewhere into that roleplay? That will be very dependent on context, but I think there's a case to be made that the Fate GM has gone a couple of sentences too early.
But I don't see any issue about it not following from the fiction.
(2) You seem to be equating
compulsion from outside the character's rational choices with
compulsion from outside the fiction. I don't think this is a warranted equation. Landon does not say something offensive to the ball guest because of a compulsion that comes from outside the fiction. (The only RPG I know of that embraces something like that is Over the Edge.) It is because, despite his best efforts and perhaps his best judgement, Landon says rude or offensive things. The GM is playing Landon's inability to help himself. The player is playing Landon's rational agency. And the player - within the game's incentive structures which include the Fate point economy - decides which wins.
(3) I'm not sure what you mean when yuou say that your character
ended up behaving in arguably suboptimal ways. Are you talking about
suboptimal within the fiction ie the character sabotaged his/her own goals? This is what Landon does if Landon's player takes the Fate point; the Fate point economy is intended to make this a richer and more intense aspect of game play. Eg and as@Manbearcat has posted, it makes it
costly (ie paying a Fate point) for rational will to triumph over irrational or self-defeating habit or inclination or personality trait. This is a real-world experience of what, in the fiction, is the making of an effort by the character.
If you mean
suboptimal in the real world, as in,
in making those decisions you undermined you own goals as a RPGer, then that seems curious and I don't quite follow.