While it's quite likely to have a device I own compromised at some point it's less likely for everything to be compromised at once. My phone can access some backends, my laptop can access some others. Full backups are accessible from either. 2-factor authentication makes compromise of all accounts less likely.
It should be possible, for someone who wants a very low chance of losing all their data, to remember 2 or 3 passphrases and compartmentalize access to servers and backups such that most backups are pull instead of push (or have restricted permission ala 'zfs allow') and compromising everything requires attacking multiple platforms all at once.
Make sure it's possible to access everything starting from fresh installs on fresh hardware; once it's clear that one device has been compromised it's best policy to begin fresh on all devices as soon as possible and then start restoring from backups. Have some offline backups.
To be fair, convenience trumps some of these guidelines. Security is hard and only organizations can achieve a high level of resilience since brain backups don't exist yet.
It should be possible, for someone who wants a very low chance of losing all their data, to remember 2 or 3 passphrases and compartmentalize access to servers and backups such that most backups are pull instead of push (or have restricted permission ala 'zfs allow') and compromising everything requires attacking multiple platforms all at once.
Make sure it's possible to access everything starting from fresh installs on fresh hardware; once it's clear that one device has been compromised it's best policy to begin fresh on all devices as soon as possible and then start restoring from backups. Have some offline backups.
To be fair, convenience trumps some of these guidelines. Security is hard and only organizations can achieve a high level of resilience since brain backups don't exist yet.