I do consider the master password to my password manager as my "thing I know", and not the randomly generated passwords it stores. But you're saying that have-vs-know is not really important in the security space, that was mostly just a handy shorthand?
so are passkeys just a simplified workflow version of the complicated dance I have to do on windows to get git commits to push easily with the public key from putty-gen? But also the private key is sometimes locked to the device it was generated on? I guess I should read some actual technical docs on em.