I am a big believer in ‘Finder Zero’, but I also believe in backing things up. So I regularly backup things like RAW files for Photography, disk images from servers, and archives from long forgotten projects.

In general, backing them up to my desktop is enough. That’s the backup. Indeed. I actually use these files so little that I need to remember to mount the disk before using it with

 sudo mount /dev/nvme1n1p1 bigdisk/

Normally after I’ve had to find the disk with lsblk.

Every few months I back up that drive to a big external drive with one of:

rsync -aHAXv --exclude=lost+found --info=progress2 --ignore-existing /home/joe/bigdisk/ /media/joe/1TB\ externa/bigdisk/ #(when I want super fast) 
rsync -aHAXv --exclude=lost+found --info=progress2 --size-only /home/joe/bigdisk/ /media/joe/1TB\ externa/bigdisk/ # (when I think I might have edited the archive a bit)

…and store it securely. About once I year I take that external drive to a secure external site and back it up there.