Tomelena I was using a rooted device before (a 4a), because I don't like being told I don't have permission to access or do things on my own devices. How often will I be told that on graphene?
GrapheneOS is not a "modder ROM". It is possible to build a private fork that is rooted, but that breaks the security model and will not receive a lot of support on this forum. Similarly, tweaking via adb will generally be discouraged.
The expectation is that debug builds and adb and developer options are intended for use by Android developers and app developers for debug devices without personal private data, whereas "daily driver" devices with personal data have the full Android security model in effect. If that model is distasteful to you then GrapheneOS might not be a match.
Please note that I do not speak for the GrapheneOS project.