After following advice here, I have found myself stuck in a loop. Only the Wayland version works, but I need the normal edition. I no longer care about getting KDE, I just want my laptop fixed. It has an old Nvidia Quadro 2013 if that helps.
I found that running sudo apt uninstall kubuntu-desktop and sudo apt autoremove and then rebooting seemed to fix the problem. I still don't have KDE, but I don't want to risk my PC trying. I also added gnome tweaks, I don't know if this made any difference.
I found that running
sudo apt uninstall kubuntu-desktop
andsudo apt autoremove
and then rebooting seemed to fix the problem. I still don't have KDE, but I don't want to risk my PC trying. I also added gnome tweaks, I don't know if this made any difference.