If your TOTP key is stored in the same place as your password, is it still in any sense a second factor?
If someone gets your vault password and can unlock your phone, you’re toast, but SMS as a second factor is then also compromised so what usable (since this thread started as trying to sell MFA to lay people) options do you have (other than maybe a Yubikey)?
1: https://caniuse.com/#feat=webauthn 2: https://caniuse.com/#feat=u2f
After 1Password introduced MFA (TOTP) support, it has been used widely in organizations in shared vaults so multiple people can share critical logins that use MFA. This of course means that if your 1Password account is compromised it's game over.