False.
Pope Innocent III in the Lateran Council of AD 1215, Unam Sanctam, the Papal Bull of Pope Boniface VIII, 1302, and Pope Eugene IV’s Bull Cantate Domino, 1441, all refer to those who have rejected the true gospel, Pope Eugene IV makes the statement about the pagans, Jews, etc… so this classifies them like the Arians, Monophysites, Ebionites, who heard the message of Christ’s gospel. It is not talking about those who have not heard the gospel. The ones that these decrees are considering are those that have heard the message. If they had heard the message and obstinately stay outside the Church, they cannot be saved. Notice that in this decree, just like the first two mentioned, the decree does not say, “Well, if those pagans and Jews, etc. have never heard of the gospel, they cannot be saved.” This is fully consistent with what the Church teaches now.
From the Catechism of St. Pius X on the Ninth Article of the Creed:
"29 Q: But if a man through no fault of his own is outside the Church, can he be saved?
A: If he is outside the Church through no fault of his, that is, if he is in good faith, and if he has received Baptism, or at least has the implicit desire of Baptism; and if, moreover, he sincerely seeks the truth and does God’s will as best he can such a man is indeed separated from the body of the Church, but is united to the soul of the Church and consequently is on the way of salvation."