Your words are reflected well in Vatican II’s Ad Gentes #7:
This missionary activity derives its reason from the will of God, “who wishes all men to be saved and to come to the knowledge of the truth. For there is one God, and one mediator between God and men, Himself a man, Jesus Christ, who gave Himself as a ransom for all” (1 Tim. 2:45), “neither is there salvation in any other” (Acts 4:12). Therefore, all must be converted to Him, made known by the Church’s preaching, and all must be incorporated into Him by baptism and into the Church which is His body. For Christ Himself “by stressing in express language the necessity of faith and baptism (cf. Mark 16:16; John 3:5), at the same time confirmed the necessity of the Church, into which men enter by baptism, as by a door. Therefore those men cannot be saved, who though aware that God, through Jesus Christ founded the Church as something necessary, still do not wish to enter into it, or to persevere in it.”(17) Therefore though God in ways known to Himself can lead those
inculpably ignorant of the Gospel to find that faith without which it is impossible to please Him (Heb. 11:6), yet a necessity lies upon the Church (1 Cor. 9:16), and at the same time a sacred duty, to preach the Gospel. And hence missionary activity today as always retains its power and necessity.
The Hebrews 11:6 reference is worth a look here:
Heb 11:6 And without faith it is impossible to please God, because anyone who comes to him must believe that he exists and that he rewards those who earnestly seek him.
And I think
Genesis315 in this thread has given enough examples that reflect a sentiment of “exceptions” to formal union with the Catholic Church. Or perhaps better said, union to the Church in extraordinary means. I agree that the possibility of being saved while not a formally recognized Catholic should not be watered down. We must evangelize, as
Cats and Dogs, and Ad Gentes exhorts, in accord with openly bringing all persons into the Holy Catholic Church, which is His body.