The point of yours I was responding to is: "I know exactly what people need and my ideas are all rational and brilliant while other's are stupid and irrational" So given that, as opposed to the familiarity issue (which I wasn't talking about - but is another intersting topic), I don't see any false dichotomoy in my response.
I think for art you can look at a work in 2 ways: the subject and the style. The subject can and usually is highly influenced by the buyer, but the style of the artist, which I argue should be a manifestation of the artist's core values, should not be influenced. If it were, the artist would lack core values and consistency - which is never the case (that I know of) for meaningful artists. So again, the buyer chooses the artist for their style, and then goes from there on possibly suggesting a subject (such as a portrait), not the other way around.
You can easily argue that Apple is taking this same approach to technology. They present a distinct style of products - usually highly designed/integrated and simple to use (some would argue almost inspiring to use) in their many different products, but the type of product they make is highly influenced by what people want. For many, Apple products might be too simple or too expensive, but there is a growing group of people willing to pay extra for Apple's style of technology.
Now, if Apple were to change their style based on market research for every product, that would be the death of the apple brand as we know it, and they would morph into yet another cloning company. The familiarity idea you were talking about also breaks down with the Apple example, as who knew they wanted a Mac before it existed? It certainly wasn't familiar, nor was the Iphone, etc. But that issue is another topic. My point was that to be a successful artist adherence to a core set of values is key (in the case of business you could call it branding). This issue shows up alot in music, where people will find that a band has "sold out" by changing their unique sound to appeal more to a mass audience thus losing those original fans.