Melania
I'm digging this classic, demure young ladies thing
Stop thinking in such absolutists terms, for God's sake. There are multiple points of value in telling kids there's a Santa 1.) it makes the holidays different and magical- these days are unlike other days, and that makes them special and fun 2.) It's a way of concretizing the idea that there are long-terms effects to our behavior in kids of an age where their abstract reasoning faculties are not completely developed- because unless your siblings are psychopaths and so are their kids, they tell the kids to behave, they behave, toys show up on Xmas and suddenly they understand there is something other than the immediate value of controlling their immediate behavior 3.) When they learn there is no Santa, they learn that not everything they hear is something they should believe, and the circumstances are such that they will remember this lesson on a visceral level. This is a tremendously valuable for young people as they move closer to adulthood.
Instead of assuming that all traditions are valueless, try to find the value in them.
You notice that the papers keep spinning it like he declined an offer, when what he said was that he asked to not be considered- so much worlds apart
Use it as a teaching moment. People need to raise their kids, that involves talking to them.
Why'd you lie to meeee?!
"Because you were younger then, and we tell those stories to make the holidays fun and special for little kids. You're older now. You're a big kid, and you don't need those stories to know that the holidays are special. And I'll tell you another secret now, because I think you're ready for it. Do you want to know what the secret is?"
Okay
"What makes the holidays special isn't Santa, the decorations, or even the toys- it's spending time with the people closest to you and showing that you love them and care about them (or Jesus, depending on what you're into). We told you those stories to make the holiday more fun for you, because our parents did the same for us. Did you have fun when you were little, waiting for Santa?"
Yes
"See? And now you're part of this family tradition. This is something we older family members do for the little ones to make the holiday more fun. So, make sure not to ruin it for the little ones, okay? That wouldn't be fair to them."
Etc etc
Telling stories to kids isn't a problem of itself. The problem comes when people lose sight of what stories are for- teaching, sharing traditions, and eliciting emotions. Seriously, I don't know if this a low-energy shill thing, but if you're a real person, broaden your viewpoint. Start trying to think metaphorically and symbolically. The greater part of our lives are not expressed explicitly.