update-grub is a shortcut for grub2-mkconfig -o /boot/grub/grub.cfg (I believe it adapts to UEFI and BIOS systems) that is only available in Ubuntu. Maybe this could be brought to Fedora too? I've seen people confused that update-grub doesn't work in Fedora. Also, update-grub is way easier to remember and helps inexperienced users in a recover procedure.
update-grub
grub2-mkconfig -o /boot/grub/grub.cfg
The help doc is a bit confusing regarding updating grub, because it mentions three commands and it doesn't explain clearly which one to use.
In general, you shouldn't be doing it at all. The update-grub Debianism doesn't really help anyone, and on Fedora systems, that file is static and doesn't change since we use the Bootloader Spec since Fedora 30: https://fedoraproject.org/wiki/Changes/BootLoaderSpecByDefault
Metadata Update from @ngompa: - Issue close_status updated to: Won't fix - Issue status updated to: Closed (was: Open)
This issue has been migrated to Fedora Forge: https://forge.fedoraproject.org/workstation/tickets/issues/355
Please continue any further discussion there.