He knew, he just didn't give a shit until Rudolph happened to be useful. It's a capitalist moral sorry, showing that you will get things and be treated well only if you are useful to the rich overlords.
Mine was that those in power will turn a blind eye to the mistreatment of those with divergencies, unless said divergencies prove to be useful to the capitalistic machine.
Santa is strictly non interventionist because he's a child-friendly metaphor for God. A child asks, "why doesn't Santa help Rudolph?", and the lack of satisfying answer to that prepares them for when they're an adult and they ask, "Why doesn't God help the poor?".
Rudolph getting put in front of the Reindeer team is the meek inheriting the Earth.
Why the fuck does the song assume we know Dasher, Dancer, Prancer, Vixen, Comet, Cupid, Donner, and Blitzen, but it has to ask if we recall Rudolph, despite him being "the most famous" reindeer of all?
Back when it came out, it was a tongue-in-cheek joke. “SURELY you must remember the most FAMOUS reindeer that we certainly didn’t just make up, right?!”