Passkeys are built on the FIDO2 standard (CTAP2 + WebAuthn standards). They remove the shared secret, stop phishing at the source, and make credential-stuffing useless.
But adoption is still low, and interoperability between Apple, Google, and Microsoft isn’t seamless.
I broke down how passkeys work, their strengths, and what’s still missing



The biggest disadvantage:
More eggs in the American megacorp basket for more people, yay
Currently I use a FOSS (I think?) password manager, BitWarden, that supports passkeys. I use it across Mac, Windows and Android so I’m while my passkeys are locked yo the password manager, I am not locked to any of the aforementioned megacorps.
I use BitWarden too. OS , device and browser agnostic is a win
But I imagine the vast amount of people will use whatever their platform is pushing, so Apple Google or Microsoft. And in 5 years time “3rd party passkeys” are not “secure enough” and blocked by the OS. (Ok that’s a bit tinfoil hat, but Google’s recent Android app developer verification scheme is fresh in mind)
Your password hashes (assuming they even hash them) already live on their servers…