Interesting, and I tend to agree, but what about Rococo? There's a style that was once very popular but is hardly simple. It's probably true that simpler is better in design but I think we need to be careful and even to recognize from time to time that this may be an assumption we are making. It may be that that the universe is not explained by a few simple laws but instead is a Baroque accumulation of details and frills (unlikely). When looking for good design or trying to produce good design perhaps we should also challenge, or at least think about, the idea that the best design is going to be the simplest, perhaps all those curliques are needed.

Of course, just because Rococo was popular for a time doesn't mean it was good design. I think Rococo is the grandfather of kitsch.
Nevertheless, post-modern architecture has reminded us that the human instinct for decoration remains powerful. Even so, the aesthetics of decoration are subject to the same principles as functional design when it comes to things like simplicity and elegance. For some reason, no one seems to prefer "messy" in either context.

For Lispers interested in objectivity in asthetics, go get Richard Gabriel's _Patterns of Software_. He discusses Christopher Alexander's work on the subject. There's a lot of great material in that book on a number of topics, actually, but I found the writing on asthetics to be particularly eye opening.