My father told me he wanted to make USB flash drives of all the scanned and digitized family photos and other assorted letters and mementos. He planned to distribute them to all family members hoping that at least one set would survive. When I explained that they ought to be recipes to new media every N number of years or risk deteriorating or becoming unreadable (like a floppy disk when you have no floppy drive), he was genuinely shocked. He lost interest in the project that he’d thought was so bullet proof.
I’ve got photos in Flickr dating from 1999 onwards. Ten thousand or so of them, and a couple of the early ones are now corrupted.
But they are my “other backup” for Google photos so I don’t mind too much. I also have a USB Blu-ray drive at home that I use to periodically burn M-Discs that I hand out to a few relatives.
That’s about as good as I can conveniently do for backup, and it’s probably better than the single-point-of-failure box of negatives that my parents have in their cupboard.