I have seen some photos of Christmas theme 2-rail layouts in magazines and videos. Most of these were built years ago and the tradition has been maintained by new volunteers.
I have been to many train shows all over the country. I have never seen a 2 rail O scale themed Christmas layout in person. I was at the Cal-Stewart meet in Ontario, CA last weekend. There was a wonderful and huge 3-rail Christmas layout but nothing in 2 rail. I don't recall seeing any 2-rail O gauge layout at the show. There were layouts in S, N, Standard O, and Lego gauge.
I think the answer to your question is that 2-rail Christmas O gauge layouts are probably out there but they are very few in number.
Joe