Since switching to the T480s I had some scaling problems running Budgie. As it turns out, a lot of these problmes come from using X instead of wayland. I had never used wayland before but figured out, if Fedora and Ubuntu use it as their main display server, I could give it a try.
Apparently GNOME automatically installs with option to start the desktop environment with wayland instead of X but due to some bugs in LightDM I couldn’t select GNOME with Wayland as my DE. That’s why I switched to SDDM, the default desktop display manager of KDE.
pacman -S sddm && systemctl disable lightdm && systemctl enable sddm later I got SDDM up and running and was in fact able to select GNOME with wayland.