Perhaps it is in part the contrivances that make the play gameful.
It is interesting how RPG play has developed. I've observed a tension between what one could call immersionist play, where the player aims to live within their character and world, and authorial play, where players aim to collectively develop not only a story, but perhaps more importantly opportunities to develop or reveal truths about their characters. For many, the latter is preferably pressured and intense.
I feel a bit unhappy with your use of the 'immersionist' in this context, as it would tend to indicate that there is LESS immersion in character in a game that is more 'authorial' to use your term. I mean, the argument gets made that 'meta-game processes' break immersion. Its one of those kinds of statements that cannot really be examined, its purely subjective. I just maintain that my identification with my character is no more difficult because of that than because of all the fairly contrived stuff that goes into "you are a party" or whatever.
@pemerton has also pretty consistently argued that there are other deal-breaking aspects, like the way in which the character's understanding of the world has to be fed to him, where it would be inherent in reality, and that the authorial activity, in his opinion (which I tend to agree with), better matches with a verisimilitudinous experience of being the character.
I have been thinking about whether one way to look at it is that immersionist play places the player-character in a subjective mode, while authorial play is occasionally objective: the player becomes conscious of the mechanics and fiction, and their character as their subject. In a way, immersionist play is what historically much RPG play assumed players would do, while objective play is what much RPG gave to GM. However, perhaps greater confidence and mastery of the medium leads participants to feel they can, and then want to, contribute on both layers. While at the same time a native familiarity with video and games makes the mechanics feel more natural, and less visible and jarring... implying that for them it is not non-immersive to also consider and apply the mechanics. It's access to the full vernacular.
I don't know, I suppose there are factors which account for these preferences, though they may be so personal and non-specific as to be beyond analysis in any realistic sense.
That creates a space for gameful contrivances of the sort discussed in the second part of the OP (in relation to TB.) Players with a native grasp or conversance with modern forms of story and RPG as game, can be afforded by game designers who, too, have a strong grasp or conversance, and a body of tools/design-patterns to call on, to better frame and employ contrivances. For example, where they are systematic and not simply random pulls from lists.
I think, though, it is a legitimate criticism of TB (at least TB2, which is all I've played) that the process of play is VERY all-encompassing and thus you find yourself heavily 'in the meta'. Where with a game like Dungeon World as a player I often find myself focusing almost entirely on the fiction, that is hard to achieve in TB2. The difference being DW is much less structured above the 'participants make moves' level. Probably the main thing that happens on the player side above that level is the GM may ask the players, out of character, questions, and then use the answers. Actually I don't think DW intends those questions to BE out of character, they are addressed to the characters, not the players. However, they are likely to provoke 'player side' thinking as "Do you think there's an ocean to the east?" COULD be asked of a character, but they would never think "well, should I say 'yes' and signal that I want to go sailing or 'no there's a desert' and signal something else?"
