And as a Christian, I really wish we could separate "the mass of Christ" celebrating His birth, from all the other winter solstice trappings. I could celebrate both the religious holiday of Christmas and the secular holiday of winter solstice, if we could really separate them. We've dragged in things like Christmas trees, and given them a religious symbolism, and I have to fight through the secular to observe the religious.
The secular bits aren't celebrating the Winter Solstice, though. That's a religious celebration in itself, or a spiritual one at least for those of us who observe it but who aren't religious.
The secularisation of Xmas is one of the drawbacks of being a dominant religion. It gets simplified, genericised bastardised even, because it's 'tradition' or just What We Do instead of coming from actual religious observance.
There was also some intentional conflation of Xmas with things like the Solstice to gain that dominance.
Plus those of us who do celebrate the Solstice don't want the secularisation problem either.
When I lived near Scranton, Pennsylvania, there was an incident that it became public knowledge that a Wiccan group had held a Solstice celebration. The region is overwhelmingly Christian and most there did not take it well, even going so far as to argue that Solstice celebrations began only after Christmas was established. The furor continued for two full years and it lead to banning of all religious use of a town-owned facility that was managed as a rental hall when one faction of it demanded the town prohibit the other from ever using the facility. Part of the outrage went into incorrect claims that Christmas predates Solstice celebrations and the latter was only created to "attack" the former.
As it would happen there would subsequently be similar outrage because a small town in the area hadn't decorated one year. They had been unable to afford to replace their decorations after the old ones were no longer up to electrical code ($50,000, which worked out to $25 per resident - no small cost,) but so many there insisted it was due to a motivation against their religion.
I had to look it up the details because it's been so many years but I did remember being raised with some claiming religious significance of the plants. The traditions were that the blossoms represent the star of Bethlehem and the red leaves (which are due to specific cycles of light and dark for several days) represent the blood of Jesus. The latter always struck me as a curious one for the time of year and it felt like a desperate attempt by some people to claim religious ownership of the plants.