I don't like them, they offer no advantages to logins with random passwords. They would only be more secure if they were forced to be stored on hardware devices like Yubikeys, which almost never happens in practice. In reality it's true that they can be dangerous because they can be set up in a way that doesn't allow storing them in software and using them on multiple devices, and such device-bound passkeys will eventually lock you out or be reset in the same way as password+login (usually just by email).

The standard and implementations are also unnecessarily complex and obtuse. IMHO passkeys are not a good technology.