It's a ridiculous label to apply to Philip Glass. He would likely reject it himself.
The word "avant-garde" comes up not once in Philip Glass's Wikipedia article [0]. The only uses of the word "experimental" are in reference to his early interest in experimental theater.
Philip Glass is easily the most popular, mainstream living music composer. His music is extremely "listenable," and inoffensive to the casual listener. Calling him avant-garde is a complete disservice to what he has actually accomplished in his career. It's more avant-garde to call Philip Glass avant-garde than his music is avant-garde.
The word "avant-garde" comes up not once in Philip Glass's Wikipedia article [0]. The only uses of the word "experimental" are in reference to his early interest in experimental theater.
Philip Glass is easily the most popular, mainstream living music composer. His music is extremely "listenable," and inoffensive to the casual listener. Calling him avant-garde is a complete disservice to what he has actually accomplished in his career. It's more avant-garde to call Philip Glass avant-garde than his music is avant-garde.
[0] https://en.wikipedia.org/wiki/Philip_Glass