Simpler and repetitive does mean worse - for you. I actually agree with you, but I know plenty of people that love club/dance music, which is about as simple and repetitive as you can get. I think it's important to take the context of the music being played/performed as well: a simple, repetitive piece would likely not be received well in an orchestra hall, while a song with complex melody, deep lyrics, and rich harmony would likely be skipped at a football tailgate party. Music serves several functions in many different environments, and labeling a piece or style as universally worse is almost never true.