I don't think people have really thought this through- with the exception of Yedida.
I have yet to meet a Christian that "defends Christmas" based on scripture or dogma. It's just a holiday. It's a chance to celebrate something important in history- to Christians a most important event. It's just a day set aside for that. I don't think any serious scholar thinks Dec 25th is Jesus' birthday (nor is sukkot seriously considered for that matter, though it preaches well to this crowd).
As for the paranoia and fear ascribed to the date Dec 25th or to having a tree with decorations etc- I wonder what people are afraid of. Demons in the tinsel? Almost every day of the year could be attached to some kind of pre-Christian celebration in some part of the planet. God redeems sin and sinners, so dates on the calendar is not too big a task for him, and it is up to
us to make those times holy- "redeem the times". What's more, if you are that afraid of paganism- what on earth do you think of some of the Laws and holidays in the Torah? Piles of it is pre-dated by pagan Egypt and Canaan.
Further, all this talk of "The Lord's Feasts/festivals/times" is a bit of psycho-babble to me. They are holidays for ISREAL. God doesn't need days off to remember things, but He gave them to the Jewish people so we could remember what He did for us. They were not given as a law for Gentiles to follow. They come from the Lord, but they belong to the Jewish people. Can we please own them?
Why are there so many self-hating Gentiles?