It’s a combination between KDE 6 and Wayland, which required support in the Nvidia drivers. I remember running Nvidia on KDE 5 and had zero issues compared to now, but we’ll just have to wait. Some issues are just configuration changes that needs to be implemented by the distro mantainers (literally a one line fix on a conf file which was communicated by KDE but not picked up)

I do it manually, but I don’t have a lot of dependencies. Download the main package, install it, check the error message for the package it needs, download the new package, install the main package again… For python stuff pip download will also get the dependencies. Maybe you can use the Debian website since it lists the package dependencies and allows you to download from the website the deb files. You can probably automate with a bash script some stuff.

Ubuntu server just asked me if I want to upgrade to V24, I don’t know when I’ll take time to do that :p