> Doing it right is exactly the thing that makes this impossible. [...] do you really think that database will never be breached? It would become the prime target for all attackers in the world.

Critical data is always better in the hand of a few (trustable) than in the hands of many.

That is currently the exact reason why you are using Paypal instead of giving your credit card number to everybody.

That is the exact reason why you are using a password manager.

A lot about security is about who you trust, and for how long.