Agreed. Everybody talks about encrypting backups like it's common sense, but almost nobody talks about the risks involved with failing to back up the encryption

Agreed. Everybody talks about encrypting backups like it's common sense, but almost nobody talks about the risks involved with failing to back up the encryption key itself properly. The entire integrity of the backup then depends on that sensitive piece of data, and it's not something that can be openly shared by its nature, or included in the encrypted backup itself. It's even deceptive if your measure for success is restoring the backup to make sure it works properly, because there is now an implicit assumption that the encryption key is still valid and undamaged the next time you restore. I wish backup tools like Duplicity would warn you about the risks of encrypting backups instead of warning the user if they disable encryption, because encryption has the possibility of rendering all those backups useless when the moment to use them finally comes. I have a similar feeling that large swathes of my digital life would be rendered permanently inaccessible if 2FA was enabled and my device was rendered inoperable. (That's why I keep meticulous physical backups of emergency keys.) I think 2FA and the like should be considered a tradeoff with its own inherit risks and benefits, instead of a universally better option than randomly generated 80-character passwords alone.