Sure, it's wasn't only for personal backups. My main driver is to significantly reduce disk usage on the phone. A single app to serve as a database for all other android apps would immediately solve a lot of issues we see today. 

Its even better if it uses WebSockets locally. Then client devs don't need to change anything and users just need to add their local phone relay to their list and boom, everything now runs mostly locally. 

Thats why a full relay is useful.