[brantonb]

There are differences between iCloud and local backup. For example, iCloud backup doesn’t backup your Notes or Health data but local backup can. Sync != backup — without a backup, if you sync a bad change you’ve lost the data.

https://support.apple.com/en-us/HT204136

[r00fus]

Both of these are stored in iCloud (if you enable) and are backed up in the cloud (and E2EE). All other large repositories of data are not sourced from my Apple devices