Comment by IMSAI8080

I think it comes from a marketing exaggeration of what the card could do. None of the cards of the day could actually produce their own box art (in real time) but the art implies they could in a way they can get away with. It follows the tradition of box art on 8-bit games wildly exaggerating what the in-game graphics might look like and they'd sometimes post a tiny disclaimer in the corner.