I've flipped my stance on this. I used to be pretty pro passkey, but after using them for a while what I've observed is:

1. There's very low consistency in implementation, so while I understand the problems passkeys solve, it seems like every vendor has chosen different subproblems of the problem space to actually implement. Does it replace your password? Does it replace MFA? Can I store multiple passkeys? Can I turn off other forms of MFA? Do I still need to provide my email address when I sign in (Github actually says No to this)?

2. The experience of passkeys was supposed to be easier and more secure than passwords for users who struggle to select good passwords, but all I've observed is: Laypeople whose passwords have never been compromised, in 20 years of computing, now deeply struggling to authenticate with services. Syncing passwords or passkeys between devices is something none of these people in my life have figured out. I still know two people in their late 20s who use a text file on their computer and Evernote to manage their passwords. What is their solution for passkeys? They don't know. They're definitely using them though. The average situation I've seen is: "What the heck is this how do I do this I guess I'll just click save passkey on this iOS prompt" and then they can never get back into that service. The QR code experience for authenticating on desktop using mobile barely works on every Windows machine I've seen.

3. There is still extremely low support among password managers for exporting passkeys. No password managers I've interacted with can do it. Instead its to my eyes become another user-hostile business decision; why should we prioritize a feature that enables our users to leave my product? "Oh FIDO has standardized the import/export system its coming" Yeah we've also standardized IPv6. Standards aren't useful until they're used. "Just create new passkeys instead of exporting" as someone who has recently tried to migrate from 1Password to custom-hosted Bit/Vaultwarden: This is the reason why I gave up. By the way, neither of these products support exporting passkeys.

It might end up being like USB-C where its horrible for the first ten years, but slowly things start getting better and the vision becomes clear. But I think if that's the case: We The Industry can't be pulling an Jony Ive Apple 2016 Macbook Pro and telling users "you have to use these things and you have no other option [1]". Apple learned that lesson. I'm also reasonably happy with how Apple has implemented Passkeys (putting aside all the lockin natural to using Apple products, at least its expected with them). But no one else learned that lesson from them.

[1] https://www.cnet.com/tech/your-microsoft-passwords-will-vani...