Anyone owning a computing device in the days of Microsoft's reign was able to use any programming language in existence (pretty much) to do development for their device. The APIs were accessible and libraries and technologies played with each other. Mostly because they were around some common lower denominator (e.g. a C or lower level API). You could install anyone's software without needing an intermediary. It was clear that you owned your device, you owned your software and you owned your data. They didn't force other software vendors to pay them a fee. It wasn't Microsoft that broke all that. Microsoft is only playing catch up there.
I don't know Windows Phone 8 at all but if all you're saying is right then that sucks and I won't defend Microsoft there.
SaaS is just another facet of this multi-pronged attack on the user.