I believe LOS still does userdebug builds, so you get root over adb by default. It is pretty much impossible to create a usable local backup on official no-root Graphene builds with the recommended re-locked bootloader.

I switched to Graphene with my new phone. It includes SeedVault which is unable to backup most of my apps and ADB backup works with even fewer (deprecated by Google). So only things I could sort of backup were apps that had their own config/data export options. The stupid, "we know best" restrictions from being able to copy between user profiles also made backup and restoring a PITA (upstream android stupidity, not Graphene specific) It was a few days later before I was back to where I was before having to restore stock OS to get a warranty repair (GrapheneOS does not include repair mode or some such thing that the Google service place required). If I was still on a rooted phone, it would have taken a few minutes to restore everything.