But it's not that though. They're hosting an encrypted version that they don't have the keys for. They are doing the backend sync for you, and writing the clients that YOU run, that sync yuur passwords everywhere.

To suggest they have a copy of your passwords is to misunderstand what they're doing. It's the same as saying you host your Keypass on Dropbox so now Dropbox have a copy of your passwords/secrets.

The value they are providing is seamless sync between a huge range of platforms/devices and making it as frictionless as possible to entry your password when you need to (biometrics to unlock the vault, browser addons to seemlessly enter the passwords etc)

Your Dad has a single point of failure for all his accounts. That's not a win.