The Market Chooses You.
When the husband and I were selling our house a couple years ago, we decided a fresh coat of paint would make it more appealing to buyers. We decided to paint the inside walls all white, so as to avoid offending any potential buyers with our own sense of style. Thinking back, I think we made the wrong call there.
Painting the walls white is the same dilemma faced by websites wanting to appeal to 'everybody'. By avoiding off putting potential customers with character or style, a site with minimal or bland styling can fail to appeal to anyone. Most websites need to help visitors feel that they've come to the right place with a reassuring look and feel. (Google's minimal styling works because Google's main function is provide content and send visitors on their way. It's deliberate and well-tested, I assure you.)
Any for-sale house doesn't need to appeal to absolutely everyone. In fact, it's targeting a very specific segment of the population - potential house buyers. More specifically, people considering living in your neighborhood, with a budget somewhat in the range of your asking price. Consult with your real estate agent if you must, but do paint those walls.