a big problem with passkeys is that there is a lot of flexibility in how it is rolled out with a given site or app. Some sites ask your browser for a passkey as soon as you hit the login page. Some sites you need to enter your username/email address first before you're prompted. Some sites a passkey satisfies both password + second factor. Some sites you need to enter your password and the passkey is the second factor. Some sites you don't need a password but do need the passkey + a second factor (usually SMS)

This is on top of the confusion around enrolling passkeys in your device and synchronizing them

I am a big passkeys fan, and use them on every service I can, but they leave a lot to be desired in terms of user experience. Not sure all of them are solvable, either. The platform vendor side can be fixed: vendors can better integrate with each other to make your passkeys available on every device. But, the issues with how they work across sites and applications is probably not solvable