Modern backup would simply state “API keys and settings are here:”, and a link to collaboration platform closed after 3 years of existence.
The FSF used to sell these wonderful stickers that said "There is not cloud. It's just someone else's computer."
"Stickers from various FSF campaigns - Print out copies of our stickers for your own uses, local conferences and more." https://www.fsf.org/resources/stickers
For anything more than few machines there is bacula/bareos (that pretends everything is tape with mostly miserable results), backuppc (that pretends tapes are not a thing, with miserable results), and that's about it, everything else seems to be point-to-point backups only with no real central management.