There is something else from this I think most bitcoin security guides miss. Basic security is taught as the CIA triad.
Confidentiality, only the people I want to know my seed know it. - well covered, use an airgapped hardware wallet.
Integrity, my recording of my seed won't change our easily be damaged. - well covered, metal seed backups.
Availability, the people I want to have access will not lose access. Poorly explained in most bitcoin security guides. M of N multi-sig with partially custodial inheritance services like nunchuk or unchained is the best solution I know of.