I'm less worried about the size and more about something breaking when doing a recovery.

Let's say you're running Fedora with Gnome and you want to switch to KDE without doing a fresh install. You make a backup, then go through the dozens of commands to switch, with new packages installed, some removed, display managers changed etc. Now something doesn't work. Would recovering from the restic backup reliably bring the system back in order?

The tool from the original post seems to be geared towards that, while most Restic and rclone examples seem to be geared towards /home backup, so I wonder how much this is actually an alternative.