The majority of users are not complete morons. If they understand the need to backup their private key (or wallet password, or whatever), they can do it. If they still don't do it, maybe they don't value their data. In 2026 even the proverbial grandma should know what a backup is, even if they don't understand exactly how a given private key or protocol works.

We shouldn't cater to such users and make our communication less secure because people put off making backups.