In the mood for some utterly pointless metaphysical jive? Have I got some jive for you. To wit:
The Implied Parallel Reality Theory of Fictional Reboots.
Hear me out, OK?
Every fictional universe is a tweak on the "real" world. Implied: the tweak is as minimal as can be. Thus, Man of Steel (i.e., the latest Superman reboot) plays out in a world that resembles ours as closely as possible. It's our history (Pearl Harbor, 9-11, etc.) with Superman airbrushed into the fabric of causation. Okey-doke. Now think about it ...
Granted the age of the lead actor, Superman appeared on earth sometime in 1983, watched his foster father die about the time Twister came out, and didn't reveal himself until General Zod's invasion in 2013. This means ...
In the Man of Steel universe, Jerry Sigel and Joe Shuster didn't invent Superman in 1933.
Action Comics didn't put Superman on its cover in the issue of April 18, 1938.
George Reeves didn't play him in the 1950s TV show.
Or, for that matter, Christopher Reeve, Brandon Routh, Tom Welling in their respective adaptations.
More importantly ...
Jerry Seinfeld wasn't making Superman references on Seinfeld.
Granted the "minimal tweak" hypothesis, within this universe existed a Superman analog -- an Ultraman, Megaman, Badass Man or whatever -- said figure created by the Jerry Sigel and Joe Shuster of this universe, and alluded to by the Seinfeld of this universe. If you think about it, it's kind of an interesting idea.
Or maybe not.