What I find pretentious about a lot of Prog Rock is overly complicated pieces of music that are complicated just for the sake of being complicated. I appreciate the musicianship but there is no need to play 1000 notes when you can get your point across with half that.
This is self-contradictory. Music isn't complicated based on the number of notes in it. (something I wish certain singers would comprehend) Music is complicated because of how it's played, not what notes are played. Additionally, no musician writes a complex piece because they want it to be complicated. They write it because that's how their muse rolls. They write what they feel, as any musician does, and if it's complex then so be it.