For some reason, Android File Transfer (as well as OpenMTP) apps are not able to connect to the phone unless I enable both "USB Debugging" (in Settings/System/Developer Options) and "File Transfer" in (USB Preferences).
Do I understand correctly that normally there should be enough enabling only the "File Transfer" item? Why may "USB Debugging" be required for file transfer apps to work, if I am not using adb for file transfers? Could it be because I have platform tools/Android Studio installed on my Mac alongside Android File Transfer, or is it specific to GrapheneOS security features?