What a fun vignette.
I've seen the Santa Claus is Superman idea presented before (e.g.,
here ), but your time-warping, Superman-as-the-origin-of-Santa-Claus spin on things is new to me, and I love the gentle feel of your tale.
I don't blame the time travelers for wanting to be there. I'd want to be, too.
Well done.
Joy,
Lynn