Would you?
I as a child had insomnia, so I saw through the ruse immediately. I however was under the impression that they needed me to play along, so I went with it until we ended up having a talk about how much I already knew.
A lot of what enables the Santa delusion is over a cultural understanding that a lot of people's parents are reinforcing the same lie. A lot of why the ruse works is over how their environment seemingly supports the idea, rather than it just being the parents alone. As a child who had an early glimpse into how Santa was not real, this gave me an early understanding of the impacts of Propaganda.
I'd build my kid a miniverse of myths that gives it the purpose to break out of them. The insanity would be for me to watch
Until you accidently make a cultist who has the lore outlive you, towards your children's children.