It is not deceit.
What is wrong with you! IMO, you stymied your children’s imagination; which leads to creativity, and that can impact the world. What did they say to their friends growing up? How many children did they impact because their parents were so cynical, and bah, humbug: Even Scrooge came around. Your poor babies. I feel sorry for them. They missed the twinkle of it all. That’s on you.
Just to let you know, I am not a gift person. Christmas celebrates the birth of Christ. I go with it all, and get practical presents; Home Depot cards, dot needs new front door mat, in laws want new skillet, and handkerchiefs, new baby car seat needs a mat, etc. But, good grief, at least, I let my children experience the magic of Santa. What is wrong with you, really? Were your parents the same way you are about Santa? And, what are your thoughts on Christmas, all together? That should be interesting. Looking forward to your reply.
Also, why not let our children live in a fantasy world for as long as they can? The real world is so incomprehensible, anymore; it is more than shocking. And, being the future generation, they will have to live the nightmare that the World is today, sooner than you think.