The main thing that makes the Arduino a possibility is the compiler.
Put it simply there is not a free open source compiler for a Propeller chip. Especially one which can compile C code. While C code is not ideally suited for a Propeller it could be made to work.
Only if Parallax or someone else puts in the effort to do this can you begin to think of such a product.
With the Arduino Tre Ti are willing to put a lot of effort into the software. They are big enough to do this where as I suspect that Parallax are not. Same goes for the Intel Galileo.
Remember, important as the hobby market is to you, it is an insignificant flea bite to semiconductor manufacturers.