Very interesting :)
I personally have a... very critical approach to this 😅 Which is surely rooted in my personal taste in games and game experiences.
Depending on how we define them I tend to value "immersion" and "realism" very little compared to other elements. They are "nice to have" but don't make or break the game (which instead is was many people firmly believe 😬).
I think we would need to discuss specific examples and practical ideas. The concept of "level of guidance" is very interesting, for example. I saw a very cool analysis of how landscape design is used in the last two Zelda to invisibly guide players towards an almost linear progression, without ever placing a hard block in their way.
But yeah, the fact that the whole thing can be extremely subjective makes it a difficult topic to pin down.
Like... I can't play games like Undertale and Hollow Knight.
I just can't.
I love everything about them, but the friction caused by their respective combat systems makes me just throw the controller (a metaphorical one, I am a mouse+keyboard player through and through) at the screen and rage quit after the Nth attempt.
Does this count as "breaking immersion" or is it something else?
Would I be more "immersed" if I could benefit from some blatantly extra-diegetic help but stay in the flow of the game?
Is flow (an allegedly mental state where your mind is kinda switched off while also hyper-focused on a mechanical task) a form of immersion... or is it its antithesis because it kills the illusion of "being really there" to focus on a hand-eye twitch-based reactivity?
Or...what about the UI design of Disco Elysium? It is 100% extra-diegetic, but due to its perfect match with the game's overall stylised art-style and metaphysical-inspired ideas, I would argue that it actually contributes to make the game more "immersive" as you are never taken out of the experience graphic language... while still clearly engaging with lists, points, literal dice rolls, etc.
Very cool topic indeed :D
For example... at least in TTRPGs... I stand by the idea that it is far more "immersive" to have mechanics that foster, support and deliver emotionally impactful content, rather than trying to present an arbitrary model of imagined physics (aka - it is less important to know that falling from a balcony causes 3d6 crushing damage, than it is to establish that your own brother pushed you down because of some misguided reason that you [the player] actually care about).
Immersion through personal engagement? Maybe? Or (again) is this not "immersion" but something else entirely?