Having all your data always with you stored locally (on your phone) is simpler than syncing and more private than cloud.
One OS with all your software. No need to install same app multiple times on different devices. Don't need to deal with questions like, for how many devices is my license valid for. However, apps would need to come with a reactive UI. No more separate mobile and desktop versions.
Example, you take a photos on your phone, dock it at your desk or laptop shell, and edit them comfortably on a big screen, with an app you bought and installed once. No internet connection is required.
A docking station could be more than just display and input devices. It could contain storage for backing up your data from the phone. Or powerful CPU and GPU for extended compute power (you would still use OS and apps/games on your phone with computations being delegated to more powerful HW).
This could replicate many things cloud offers today (excluding collaboration). No need to deal with an online account for your personal stuff. IMO, it would probably be less mystical than cloud to most users.