It is the duty of the Church to protect the faithful from error.
The Catholic Church has a poor track record concerning error and willful disobedience of God’s commands.
Really?
Gnosticism, Manichaeism, Arianism, Docetism, Monophysitism, Donatism, Pelagianism, Semi-Pelagianism etc.
These are just a few of the heresies the Catholic Church put down to protect the faithful from error over the course of the last two millenia. Let me know when the protestant contingent has a record that can match it.