I do this, alongside other methods.

The problem with archiving data is you always need to be prepared to use the "next big thing" once your preferred method becomes unobtainable.

I currently have :

- Photos in iCloud (Live working copy)

- Backup at home on NAS (updated nightly, snapshots)

- Backup in pCloud (lifetime, mine or theirs, no illusions, hopefully lasts a couple of months if I die unexpectedly)

- Yearly archive on external HDDs, identical copies stored in separate locations, clearly labeled "Photo backup". No encryption, no archiving, just plain APFS formatted drives that can be plugged into a computer and read.

- Yearly archive M-disc blu-ray discs, again, identical copies, stored in separate locations. One disc per year labeled as such, ie. "Photo Backup 2020". The idea being you restore them in chronological order and have a complete set.