An awkward question about the world of Harry Potter

The Harry Potter film series is an adventure fantasy about a boy Wizard and... wait, the whole world already knows perfectly well the great work of J.K. Rowling. And it's interesting that many people like to revise the "Potterian" during the Christmas holidays, despite the fact that the films do not make any deliberate accents on Christmas, but show the entire school year in its entirety. Maybe it's all about the main musical theme of the composer John Williams or the atmosphere of fairy tales and miracles ... in general, as a rule, people don't really think about it. However, this guy decided to ask a very uncomfortable question. Like, why does Harry Potter celebrate Christmas at all?