I hope you perceive my comment as on topic.
I want to rely solely on local backups and no cloud backups, and not achieve this with custom recoveries (physical security loophole) such as CWM, etc.
I noticed that on stock Android 4.3
Then I tried CyanogenMod and set Settings > Developer options > Root Access (duplicate entry also under: Settings > System > Superuser > Settings > Superuser Access) to "Apps and ADB".
Obviously "Root access to ADB" means something else (what???) but not "Run ADB as Root".