Not at all. The difference is one of how zoomed in we are on the minutae. Let's take the same mechanic character in various games.
- In GURPS or Champions we might list all the screwdrivers, the sizes of the sockets in the socket set, the length of the tapemeasure, and more
- In D&D we'd probably list that they had a screwdriver kit and a socket set or possibly a workman's toolkit and the weight
- In Fate we'd give them the aspect "Prepared Mechanic"
It's the same character who's prepared themselves in the same way - but how much we, the players, are actually tracking varies from game to game. An obvious case in actual D&D would be the Spell Component Pouch which if you treat it the way you do (especially in the 3.X days) is in a quantum superposition that potentially contains an infinite number of live spiders. But people use Spell Component Pouches because they find actually tracking the minutae boring so we don't zoom in close enough to track what's in the component pouch just as we don't zoom in close enough to track every bowel movement the characters make.
Likewise something like a "Well Prepared" character. It's not a quantum superstate
for the character. The character is well prepared. The
players just don't find tracking all the preparations they've made to be part of the fun part of the game and want to focus on what they see as the interesting parts. And the character will always
always know more about the setting than the player ever can; they are after all using all five of their senses within the setting for twenty four hours per day.
Being more comfortable with one level of zoom than another is one thing. But that doesn't mean that things are in a quantum superposition any more than characters stop existing in a film setting when the camera isn't on them. We just aren't watching that bit.