Colors mean more when you're not taking their effects on you into account. A kid playing Asteroids has no (conscious) idea about aesthetic adrenaline triggers. I wonder if the game would have grabbed me so fastly if it had been colorful; Space Duel, Atari's coin-op Vector contest meant to succeed Asteroids and its Deluxe sequel, was only marginally exciting compared with the cold vacuum of space evident on the understated screen of the single-color original.
That game, Star Castle and other early Vector contests were a bit frightening -- in a cool way -- because of their cruel simplicity. These rocks hurtling at your ship don't care how they look to you; they're not colorful or friendly. You've been placed in this predicament, and there will be no sympathy or visually comforting concessions. Deal with it. When such minimal coloring works, it really works, because it forces your attention away from being impressed by decor, and centers you on the game play itself: the raw, essential deal you're dealin' in.
I wonder if that's why the designer of 2600 Asteroids could have made such a graphically simple concept so much less viscerally exciting. The colored rocks just don't seem as threatening. -- CF