It's not sharing the device's hardware that matters, but the device's data. All your data is either on the phone (pictures, etc), or available through the phone which is always on and always authenticated to the "cloud" (Android Gmail contacts, emails, etc).
The future of computing is either that (using your cellphone as a computer), or putting 100% of your data on the cloud (so you can access it from any device). But the former has the advantage that data can be cached on the device (pictures, contacts), therefore it does not require permanent Internet access so you can work even when offline.
I think it's fair to posit that cheap cloud storage space will meet/outpace smartphone storage space, to the point where simply imaging the entire phone to the cloud is easy enough. Even if you lose your phone, you authenticate a new one and you're ready to go in the time it takes to download the image.
The future of computing is either that (using your cellphone as a computer), or putting 100% of your data on the cloud (so you can access it from any device). But the former has the advantage that data can be cached on the device (pictures, contacts), therefore it does not require permanent Internet access so you can work even when offline.