I think you're right for the most part. Apple probably doesn't want tons of variation in their products, for brand recognition. How long does it take to recognize an Apple laptop? They come in only one style that is distinct from most other laptops.

But as the author said briefly, if they are really releasing an iWatch, it would be different. It isn't an item that stays in your pocket, and the style would be one of the primary reasons for wearing it for some people. And those people who buy for style wouldn't all want the exact same watch