Non-passkey based account access still works. As in i can go into my Google/Apple/MS account settings right now and in the security tab there's a ton of different options you can set.
Backup codes, sms phone recovery, alternate recovery email are all there in all of the above.
It's no different to forgetting your password/losing access to your password manager is it? As in i've literally at points lost access with passkeys (i only had 1 at the time) and the way i got back in was very straightforward and no different to losing access to a password manager. I got an email and typed my old password and i got back in and re-setup my passkeys.
If I lose access to my password manager, I'd be substantially boned. But I'm less worried about that. It would require me to forget my password, or 1password to get pwned, go bad, or lose data.
The way I assess risk, that's less likely to happen than I am to lose my passkeys.
If I'm using passkeys but can recover my account with SMS, then why am I using passkeys? That sounds like the weak link of security. I'd rather use passwords, where I can understand what the password consists of rather than passkeys if I'm not getting an increase in security.
Account recovery with the big providers that support passkeys is two factor from what i've experienced, eg. sms+email, email+old password or sms+recovery code etc. so definitely a step up from password login.
Backup codes, sms phone recovery, alternate recovery email are all there in all of the above.
It's no different to forgetting your password/losing access to your password manager is it? As in i've literally at points lost access with passkeys (i only had 1 at the time) and the way i got back in was very straightforward and no different to losing access to a password manager. I got an email and typed my old password and i got back in and re-setup my passkeys.