The seasons are the reason for the timing of many religious holidays, because the seasons are meaningful. I say enjoy the seasons, just without the religion.

Humans need things to celebrate with each other and in groups, and winter solstice to me seems like a big one for obvious reasons, mostly to do with agriculture. I say party on...

It will happen if it is acknowledged or not.

I forgot that I had written "celebrating"---- but then the question is, is the fornication of the fictional god-dude and the fictional, so-called, 'Virgin Mary' something to celebrate?

I go to celebrations of the Winter Solstice. We have one at the Unitarian Society I belong to. The Unitarian Society is kind of like a church, without the requirement of believing in god(s). They own a building, have a Sunday morning gathering, have family activities, adult education and that sort of thing. Humans have a need for celebrations. Theists have their needs and atheists have their needs.