No, Nobara is a random remix of mutable/traditional Fedora. They even remove SELinux and replace it with Apparmor, which I can umderstand but assume is less secure. The better OS imho is bazzite.gg
On Bazzite/Atomic Fedora the base OS is already snapshotted on every update. I dont use multiple drives, but mounting them somewhere in /var like /var/home works