After the arrogance and hubris of scientism crept into human paradigms, ideas such as "demythologization" came into eventual vogue, and skeptics since have propounded their fundamentalism about things that exist and things that don't, as did religionists before their time. Two extremes, scientism and religious absolutism.
Santa Claus. Does he exist, or not? It's a childlike question, of course, but it's also a moot question, but most non-practitioners, religionists, scientism-ists, and other Muggles don't know why it's a moot question. Santa Claus is astral, and manifests as multitudinous avatars; sometimes the manifestation is strictly iconic, sometimes in acts of human charitable, joyous kindness, sometimes as gift-givers and parents, and of course as all and some of the above. And then some. Astral, living fields are conscious intelligence, entities that aren't old rags n' bones but states of being, evolving archetype-symbols that hold the promise of happiness and well-being. The ol' Saint Nick is a cozy Yuletide personification who is about happiness, joy, wonder, and love.
He has no axe to grind, and his bag is a bag of toys and merriment, not a bag of tricks to deceive into religion and other such baggage. If you're naughty, you're on his shit-list and you'll get your karma. If you're nice, you'll get toys and cozy karma. Plain and simple.
Wishing you all a Joyous Yuletide Season!