You can still benefit from adding passkeys to some sites. It will often be a little faster and/or fewer clicks than using a password, especially at sites where you have to enter a TOTP code.
For example at Github signing in with a passkey from the sign in page is two clicks. Click on "Sign in with a passkey", a dialog pops up from the browser showing the passkey it will use by default, and I click "Sign in".
With a password it is a click to have 1Password fill my email and password, a click to submit (which could be eliminated if I had autosubmit enabled in 1Password), and then it asks for a TOTP code. After the code is entered it is a click to complete the sign in.
Github's TOTP entry form is well coded, so if 1Password has the TOTP key it will automatically fill it. If you don't keep TOTP keys in 1Password you'll have to open your authenticator app and copy the code.
Considering that it only takes a few seconds to add a passkey for Github to 1Password, you'll make up the time that takes after just a few logins.
For example at Github signing in with a passkey from the sign in page is two clicks. Click on "Sign in with a passkey", a dialog pops up from the browser showing the passkey it will use by default, and I click "Sign in".
With a password it is a click to have 1Password fill my email and password, a click to submit (which could be eliminated if I had autosubmit enabled in 1Password), and then it asks for a TOTP code. After the code is entered it is a click to complete the sign in.
Github's TOTP entry form is well coded, so if 1Password has the TOTP key it will automatically fill it. If you don't keep TOTP keys in 1Password you'll have to open your authenticator app and copy the code.
Considering that it only takes a few seconds to add a passkey for Github to 1Password, you'll make up the time that takes after just a few logins.