The question is, when does a game stop being enjoyable to the typical player? When it is too hard, or the flow gets lost.
For example. journals, or highlighting of items. It is almost necessary because games tend to be built from repeating elements ("prefabs"), which are arranged in certain different ways. This allows memorizing map layouts and stuff up to a certain point; after which the gamer gets lost and has to consult help or search everything over again. Contrast this with the Real WorldTM, which has only unique items and locations that give many clues to the brain that helps to distinguish and remember stuff: Here a distinct dent in that box, here a scratch, this box is a little yellow at the bottom from the carrot juice, and so on.
What I want to say is, games rely mostly on location memory; whereas our real world gives much more clues and context; making mental clutches much less necessary.