I think what they're doing is brilliant and makes total sense (if they follow through and really start pumping out XBOX exclusive games to the Windows 10). Here's why:
As it stands right now, I have a PS4, Wii U, and a gaming PC. There's about a 5% chance I will ever buy the XBone. I don't need another black rectangular box hooked into my TV. Multiplats are played on the PS4 and PC. Exclusives are played on the PS4 and WiiU. There simply aren't enough XBone exclusives I'm interested in to warrant a 400 dollar purchase and an extra box on my shelf. But I'd be lying if I said I wasn't interested in ANY of the exclusives. I'd love to play Sunset Overdrive. I will be playing Fable Legends. Scalebound looks bloody sweet. And I'm sure there will be others. But like I said, there is little to no chance of me ever buying an XBone.
Correct me if I'm wrong, but Microsoft isn't making anything (or very little) off the actual hardware sale of a console. So, if they lose that hypothetical hardware sale from me (and others like me), they aren't actually losing any money. Just that arbitrary unit known as a console sale. Now, you could say "But hey! If they lose out on that hardware sale, aren't they losing out on potential sales of future software which have considerably higher profit margins than hardware?"
Well, yes, you would be right! Kind of. If (and only if) Microsoft goes all in on this, and REALLY pumps their good exclusives out to PC, these software sales will be converted to PC software sales. MS still gets their software sale. Thus, their bottom line does not suffer. As it looks right now, this will be purchased through the XBOX app. Which means they get to set pricing, and control things like licensing fees, etc. It's a complete win/win situation for Microsoft, despite them potentially losing a hardware sale.