Not quite sure what you mean by "integrated the rt's ability for arm cpu's into the full windows 10 " as they are completely different code sets. Nothing that natively runs on ARM will run on x86 just as much as the other way round.
You can make them both capable of running the same applications which is the ethos behind Universal Apps but the operating system itself has to by definition be written for the processor it is intended to run on.
What makes Microsoft's attitude for RT less comprehensible is that there is
an ARM build in existence i.e. the Phone build. Not only that but there is also a build for the Raspberry Pi albeit with limited functionality.
It is difficult to see Microsoft taking on Android given its price point, if a buyer is only willing to pay peanuts they have to put up with simian software. In its 1st iteration RT was an iPad beater and as such a much more viable target, they gave up far
too easily. Not only that but they end up developing for iOS, incomprehensible!