I love Phillip Glass, and think he should have gotten a Nobel, not Boring Bob Dylan. However Phillip’s genre is best suited for Halloween or perhaps Easter, due to it’s darkly intricate dirges and sky-high drama content.
In other words, you would not use Tubular Bells (Oldfield) and call it Christmas Music, cause it just ain’t so.
From Wikipedia about the South Park Christmas episode
Composer Philip Glass composes the avant-garde musical score for the non-denominational Christmas play. Stone and Parker both strongly dislike Glass; Parker, who was a music major in college, said, “I really thought you could basically tell a third grader to sit down at a keyboard and mess around and sell it as a Philip Glass album, and no one would know the difference.”