Accessory manufacturers will make accessories if they feel they can make a decent profit. With the iPhone only having one model each year (so far), a single design is all that is needed every year or two for any type of accessory. With non-iPhones, each particular model is no where near as popular or as common as an individual iPhone. If it comes to a physical fit for an accessory, you either have to make multiple accessories for different models of phones or develop some flexibility in your accessory to fit multiple devices.
Originally Posted by ajdroidx
I also brought up the point where, to me, apple products are synonymous with generic, much as "kleenex" is synonymous with facial tissue.
That was the case a few years ago. People keep calling my Nokia N97 an iPhone and did the same for my HTC Desire Z for a while. That hasn't happened to me for at least a year. With the popularity of Android smartphones, I see references to both iPhone and Android smartphone everywhere now. Unless they specifically mean the Apple iPhone, I haven't seen people use the term iPhone to refer to smartphones.