Today I installed fedora and rEFInd but the old boot options for systemd-boot from my old arch installation are still there. How do I safely remove these old components or at least hide the old entries?
According to man(1) bootctl:
bootctl removeremoves all installed versions of systemd-boot from the EFI system partition, and removes systemd-boot from the EFI boot variables.
In addition to running
bootctl remove, you can manually remove
/boot/loader, the directory containing all of the configuration files for systemd-boot.