What year was Christmas music not considered "traditional" anymore?

Most of what we call Christmas originated in Bing Crosby movies with music written in the 40s and 50s. New songs were only rock & roll versions for a while, and then came a few parodies, and then people realized that they really only wanted flashing lights. So now we have Lightmas, and the music is anything you can dig up.

BTW the season has always been accompanied by the slogans "happy holidays", "season's greetings", and "put Christ back in Christmas".