Immersion is something created by the game devs. Its what brings a game a good review. If this wasn't true than games would be reviewed on gameplay alone, and they are not.
Immersion is only a part of what brings a game a good review especially since gameplay alone can create immersion so games can have good reviews and it not be based wholly on immersion (Being that the immersion only exists because the gameplay exists). Unless your trying to say gameplay does not create immersion (In that case some of the best games of all time have no immersion because they are pure gameplay)

Back to the original topic. The def. of immersion based on your link is "To engage wholly or deeply; absorb" if they add something like a minimap and that stops someone from "engaging wholly" then clearly that took away from the immersion instead of adding to it (At least for that player). I don't see how you can possibly argue that anything they add will add to immersion when anything they add could stop someone from engaging wholly?

What I think is your confusing someone being immersed (Ex they accept the game now and all aspects of it and engage wholly) vs. something changing the state of possible immersion (Ex. you add minimap player A is no longer engaged wholly while player B now is engaged wholly therefor the minimap changed the state of immersion). Your making a pretty big assumption that anyone who plays this game will be immersed("To engage wholly or deeply; absorb") regardless of the content of the game but this just is not the case and whenever anything is changed in the game someone who possibly was immersed will no longer be immersed and a player who wasn't immersed could possibly become immersed.

P.S. if someone already mentioned this sorry I didn't read all the post.