- Ideally, it would preserve maximum security, so your keys aren’t exposed unnecessarily, but the funds are accessible to your trusted people.
This can only be done through Centralized exchanges/wallets because using non-custodial wallet the one point one can access your bitcoin is through your seed phrase/private key without it nothing can be done since you said multi sig is not a consideration here.
This definitely shows your ideal doesn't preserve maximum security.
No idea why you wrote something completely wrong. People can use Shamir's Secret Sharing to accomplish this. It is quite easy and preserves security, no CEX is needed.
https://www.ledger.com/academy/topics/security/shamirs-secret-sharing- There’s a wait period (a few days?)—during that time, you could approve or deny. If you do nothing, access is automatically granted.
Don't do this part on chain, so many things can go wrong and there are many limitations. You can use this with some key shards stored in bank vaults or other safe operators. This has a collusion by family and safe operator attack vector open, but this is a very unlikely scenario.