[andrewaylett]

I won't archive anything on portable media.

Cloud, or variants thereof, is fine -- I use rsync.net for backup and archive. But needing to manually run a backup (say, onto a thumb drive) is not sustainable, and even though the author suggests that disks (spinning rust or optical) might actually have a reasonable lifespan, I don't trust myself to be able to recover data from them if I want it.

As the author says, the limiting factor isn't technical. For media, it's economic. For any archival system it's also going to be social. There's a reason that organisations that really need to keep their archives have professional archivists, and it's not because it's easy :).