That data storage is also ephemeral. Nobe of it will last as long as a paper note, unless some human goes to the trouble of copying it all onto new drives with new software every ten years or so.
Paper lasts for centuries without any attention beyond keeping it moderately dry and away from things that eat it.
why still back up floppies if you could just move the data to a single dvd, or throw is on the SAN?
RAID is just algorithms, the actual transport doesn't matter (i.e. spinning platter and solid state both use SATA connectors).