Your completely right. They are already headed down this path and, in all honesty, have been for years. The Xbox handheld that was rumored has been axed and they basically chose to work with Asus on the Xbox Ally. The future Xbox console is rumored to be essentially a pc with xbox software. My money is the Xbox Ally is a testbed for the software for next gen Xbox (if a true standalone console is to be made).

Even 5 years ago, when working for them, the goal is to get Microsoft service on multiple platforms. The services (365, Azure, etc.)across Microsoft are what makes the company money, not products. They make more money selling Windows license to 3rd parties than the Surface product line. Their goal is to get you using their Xbox platform on whatever device you want to. As long as you’re a subscriber, they honestly don’t give 2 shits on what device you use.