Solus Plasma running Wayland here.
All I have ever needed to do went like this...
From Terminal
sudo eopkg install android-tools
adb devices
Open phone and accept secure connection to computer
adb devices
should now show phone.
Edit: Seen the obvious error here, terminal was in root after installing. It's been a while but pretty sure that I needed to start with sudo
on other Linux distros too. Kind of makes sense, ADB is a powerful tool and fully justifies root permissions.
Edit 2: Just done a reboot and tried reconnecting ADB. No root required.
I would always have connected my device after installing android tools so would have been in root to make the first run anyway. After that for all subsequent sessions just adb devices
is adequate.