Imagine you lose your computer and phone. How do you recover your digital accounts? This happens every day to someone. The most common scenario being a house fire or robbery.
Or do you demand that the user has an email with that 128-bits authn too, with a key on the same phone that was lost?
If the worry is your phone getting lost then use a password manager that syncs to the cloud and log in with the same passkey using another device. I just got a new iPhone and logged into a bunch of things on-device using synced passkeys. It worked just fine.
Every conversation about this seems to involve someone asserting that improving upon passwords in any way at all is unacceptable unless the solution is perfect in every possible way, with the goalposts constantly moving.