I picked up a very nice 28" monitor but the graphics look terrible, especially when gaming. I have read that the kernel includes AMDGPU drivers but when I tried to install that, it installed however when I type in the command "amdgpu-install" I get the unsupported OS error.
I did try "sudo add-apt-repository ppa:oibaf/graphics-drivers" and "sudo apt update && sudo apt full-upgrade" After a wall of text nothing was updated with the second command. I also saw I could edit the gpu install script to add zorin but I do not know how to do this.
The Oibaf team has dropped support for 20.04 or Z16. Apparently, they only provide drivers for a limited window... But that would be why that did not work.
What is your terminal output for
sudo lshw -C video
It is looking for a known name like "Ubuntu". The quick work around is to modify your /etc/os-release file to say "ubuntu" instead of Zorin, then change it back once install is completed.