Have all your mails at Google, ship stuff home with Amazon, but your authentication mechanism is a trap and anti-privacy?
My company's product uses passkeys-only and it works great. We don't need to store user's email addresses if they don't want to. Because we don't need a password-reset flow. Because passkeys usually sync and backup. And if you really want, you can have multiple passkeys for your account (or multiple accounts).
I don't see how we could use passkeys as a trap. Our users find it convenient and the security properties speak for themselves.