Okay, that might have been worded wrong. I don't the device selection as being particularly supportive of more than a few limited use cases. If you're at home it would make more sense to support your Xbox streaming to your VR headset or Smart TV, you shouldn't have to go via the cloud.

If you're out, on vacation or something, then sure streaming to your phone or tablet makes sense, but you're not going to sign in to a random Smart TV or PC with your Xbox account (at least Microsoft shouldn't encourage that behaviour). That just seems like such a limited use case to me.