Was this advertised as a "Christmas" special? Or was it advertised as a "holiday" special? It's a subtle difference but there's great significance here. The only issue I can see with that is Disney has been avoiding Christmas as of late simply because of the religious connotation that it carries. Yes, Christmas was featured in the original Toy Story
, and I certainly hope Disney had no creative influence in the making of anything Pixar does. However, this is a trend that has been ongoing across all the film studios, as well as across all large corporations. Most films with Christmas featured, such as the aforementioned Toy Story
, tend to be older. Not that there's anything wrong with Christmas and its religious connotation, of course. However, corporations tend to be socially progressive, and as a result they're increasingly adopting the "Happy Holidays" approach instead of the "Merry Christmas" approach, to avoid criticism from Jewish, Muslim, Buddhist, Hindu & other religious minority groups who don't celebrate Christmas or who celebrate other holidays at this time of year, like Hanukkah. A tangible example of this shift would be Starbucks' recent cup changes around this time of year, having gone from Christmas-themed cups to cups with generic festive designs.
To answer your question, it was advertised as "a holiday event", but in the actual special they mention Christmas several times and show Christmas trees and decorations.
I can completely get where you're coming from with Disney trying to avoid criticism for focusing on Christmas only. I can get then why they wouldn't do something with like Santa or anything religious. It's just that it seems weird to me seeing specials playing on Freeform like Mickey's Once Upon A Christmas and The Santa Clause followed by this one that's basically about dinosaur toys battling each other. How can that relate to any holiday?