I'm currently working on a new version of the F-Droid Privileged Extension which will work on unrooted phones using Androids Device Owner mode. Requires adb though.
There'll probably also be a seperate version which uses a root install mode instead of requiring install as a system app.
Setting an app as device owner is usually intended to be done through a factory reset. The adb method is intended mostly as a testing tool. Android requiring no accounts being present is a weird half-way security feature it seems?
It's definitely not for your average user. But It works really well once set up. That it doesn't require root enables this on basically infinitely more devices than before. This is pretty huge! 🎉
