I was not offended by the term "simplicity" because I think you're right, a lot of music from this period is very straightforward and obvious, though pleasantly so. Even stuff a little earlier -- Mozart being a prime example -- once you figure out his method just about every piece follows the same format and after a while the sameness of his composing gets kinda claustrophobic. It's not intellectual, it's all very mechanical.
Unlike, say, Bruckner or Rachmaninoff.
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