Is passkeys just a webauthn implementation? https://webauthn.io is a similar demo I think.
It might be useful to think of passkeys as a usability extension to webauthn. You no longer need to buy dedicated security devices but can use your existing laptop and phone to login securely to your accounts. I expect my parents will start using passkeys on sites in the next 24 months. I would not have tried to get my parents to use Yubikeys.