There was also the IBM Simon, the first smartphone, before the iPhone came about. History tends to remember the product that made the category matter, not the one that technically got there first.

I never saw the Odyssey—unless it was that one night when I saw something in the window of a closed shop that was the first pong-like video game I had ever seen.

You're probably right, the Odyssey is probably as good a contender as Pong. But somehow everyone knows "Pong" (and of course Atari).