No technology in the world can protect you against every threat model and unlikely scenario.

What if the robber hits you in the head and you get brain damage and forget your password?

That's the point: passkeys, and even 2FA, address rare and unlikely threat scenarios, while defeating most common use cases (delegation by sharing credentials), and making people vulnerable to most common threats (like, losing or breaking your phone).

That is not a rare threat model. Many people use iPhones and Windows computers. Fortunately, Apple has released iCloud Passwords which lets you access passwords and passkeys from a Windows computer.

A password has the best recovery process. Period. Write it down somewhere. It's up to me, no third party.

I had more trouble with a failed 2FA than with a password.

Master password to password vault stored on metal, buried in my backyard and I tell a family member where it is in case I ever get brain damage