Every time you’re excluding something you’re excluding updating a package, while updating all the others. Then if the new packages depend on the newer version of the package you didn’t upgrade by excluding it, things break. That’s what’s happened here. Every time you use exclude to upgrade something you’re essentially breaking your system worse. That’s what the other person means by “partial upgrading”
And now that message says it’s going to completely remove your desktop environment so you’re gonna have no desktop, just a cli shell.
At this point the easiest thing would probably be to back up your home directory and whatever else you want to keep and just reinstall the system. Any other process to try and fix it is going to require more trouble and time than it would take to just reinstall unfortunately. There may not even be a way to successfully unbreak your system.