The Raspberry Pi Zero can be used as an USB device, like a keyboard. One usecase could be: automation.
More about using systemd timers: reboot
Using systemd timers instead of cron
Cron is not part of Fedora Silverblue (as well as Atomic Host). You can install (overlay) it with rpm-ostree. But it is better to avoid as much as possible to overlay packages in such systems. So, how to take advantage of systemd instead of cron?