Lucien_Lachance I'm sure you have looked already, but here is a (2022) comparison of Fairphone and Graphene.
Flashing ROMS can be a bit stressful even after you have done it a few times so a company that provides the finished product could be handy. However just like Linux every so often you still need to roll your sleeves up and get under the bonnet.
To my eyes it is mostly the fast, slim, slippery and brittle upmarket phones that have compatibility with these operating systems. If you are not going to be using a host of apps why not look at a budget level device that can be modified with the addition of Fdroid and then a gentle prune with Universal Android Debloater? There is a true learning curve here but you will be in charge of what your phone does and also have a good idea of what all those apps do.
If you feel that this might be what you would prefer here are the basic instructions for the de-bloater software.
Back up your phone data because you can never be too careful.
Enable Developer Options on your smartphone.
Turn on USB Debugging from the developer panel.
From the settings, disconnect from any OEM accounts (when you delete an OEM account package it could lock you on the lockscreen because the phone can't associate your identity anymore)
Install ADB:
From Terminal
sudo eopkg install android-tools
adb devices
Open phone and accept secure connection to computer
adb devices
should now show phone.
Download the executable it will be called something like " uad-ng-linux "
Copy into a suitably named folder.
Change file properties to executable.
The file will now be usable on Linux
Get it here...
https://github.com/Universal-Debloater-Alliance/universal-android-debloater-next-generation/releases/tag/v1.1.0
Good Luck because it is better to be born lucky than rich.
