Ottawa

I understand that it might seem a step too far, but in a way I'm thankful that someone is pushing back against the whitewashing of Christian holidays as the default.

Christmas is not secular, though in North America (and I'm sure Europe to some extent) we love to try to turn it into a capitalist holiday "for everyone." The fact that even atheists support it in mostly the same way as practicing Christians shows how effective this is.

Even in our supposedly secular society, Christianity is maintained as the norm by our continuation of their practices upheld at the cultural level. You see it in some areas where specifically Sundays are codified as days of rest, where Christmas and Easter are codified as statutory holidays, where "visible" symbols of religion are banned but Christians can keep on wearing their necklaces under their clothes, where crosses are at times not even seen as religious.

OP, you said that you "would happily attend" other celebrations, but I note that even you say you celebrate Christmas. And while you might go to another holiday event if invited, I'm willing to bet that it's a rarity and you find it to be something of an interesting learning experience. Because culturally, those holidays are othered.

I'm just so tired of us pretending that we've become a secular society while we continue to uphold Christianity in all of these ways. We still have real work to do to unlearn Christianity's cultural supremacy in the west.