Perhaps the concern should be less about 100% accuracy, or something close to that, and focus on
approximation. As many have stated there is information available to add this to the game, historical as currently constituted is no where near accurate with regards to teams and leagues anyways, and the value added would be tremendous.
Of course as with all things it could easily be an option, one that the user turns on in order to be used as opposed to something one has to know to turn off to avoid.
Personally I feel this is an important aspect to add to the game