It's just one of the many controversies of a non-issue that the right has dredged up over the years. I mean there might be some d-bag out there on the left that acts offended when they hear "merry xmas!" but I've never seen it happen in real life.
The point is more that these clickbait outrage issues are not of “the right” or “the left” broadly. They are successfully put forward to much controversy and hand-wringing by crazy individuals and Neanderthal enclaves that don’t have anything to do with society as it matters. They only get attention because they get so much attention.