honestly i feel exactly the opposite, I don’t think it’s really necessary for servers as tools like ansible are already well established in that space. Plus most servers are VMs these days which can be snapshotted easily. Also, lot of these “immutable distros” require a reboot to apply changes which is non ideal in a server, but a non issue for desktop as you can shut it down when you go to sleep.

I run fedora atomic on my desktop and laptop because i never have to worry about my system getting into a broken state, I can always roll back or even spot the problem and fix it before i reboot to apply the change. I know a lot of people say you can accomplish the same thing with btrfs snapshots, but that requires extra thought and effort on my part, where fedora atomic it happens automatically with every update.