That's totally fair, but I hope that each of those organizations has a vested interest of exposing each other; at the very least it's in the NSA's charter to protect American businesses against attacks, I have no idea if they feel this is an effective way though. So yes, it's risky. But Microsoft has all those disadvantages too, even though it's harder to get moles inside it's easier to have their stuff undetected (and in the case of the NSA it might even be done with full cooperation). Plus, the market share makes them a bigger target.

Outside probably hypotheticals, what we know for certain is that microsoft is attempting to monetize their new windows on the back of user's data.