Immersive imagining sounds to me like Detached Detail. Even if your imagined details are "realistic" and "immersive", those qualities do not move them outside of the realm of Detached.

Compare your "I like seasteading but not castles in the air." statement with a claim "I like medieval reenactment but only with historical accuracy." It seems clear to me that this is merely a preference over fantasies, not a fundamental difference in thought process.