It's easier to not engage, but since I don't know if you really don't know or not, I'll engage a little.
Nobody restores old media to a cheesy flash drive, then puts the flash drive in storage for decades. Flash media can lose bits, but only the cheapest have so little error correction that it'd matter inside of a decade.
You make a copy on a local hard drive, along with thousands of other files. When you're ready to upgrade from an older computer to a newer one, or from a smaller drive to a larger one, you make a copy.
Between the copy on your constantly being upgraded once or twice a decade drive and the copy that's on your web site (of course you've made your files available to the rest of the world), your data is fine.
