I remember cataloging and transferring a bunch of a laboratory's "Bernoulli" cartridges to Zip because they worried that they wouldn't be able to replace the Bernoulli drive if/when it failed. Then to CD, because it was incomprehensible that optical drives would go the way of the floppy. Probably a decade of data, and I think it fit on like 20 CDROMs.

For a while, I thought it was ok to just keep everything on multiple hard drives, but now it would take a special effort to get data off those IDE HDDs. And SSDs decay if not powered. It's hard to keep electronic data for 100 years.