Popes do not claim to be prophets and seers, but guardians of True Doctrine. But as for the rest, our acceptance of the Scriptures depend on our acceptance of the testimony of men who succeeded the Apostles, or if you like, came after them in time. As for Luther’s reforms. you suppose that there was no other reform movement in the Church contemporary to his, which is not the case. Indeed, Cardinal Pole, the leader of the Church of England under Mary Tudor, was one of many reformers in the Catholic Church, almost contemporary with Luther, as was Thomas More. The so-called Counterreformation was in fact the triumph of a Catholic Reform movement, the popes after 1580 has been among its leaders, and the Council of Trent an expression of its reforms.
I understand what you believe, but you are simply making assertions. Popes make claim what they will, and you may accept what they decree, but even Jews and its Majisterium, which again, unlike the Pope, the Bible explicitly affirms were given the stewardship of the Hebrew Scriptures, were not necessarily true Jews due to that fact, let alone infallible guides, and were reproved to adding to that which was written. (Mt. 15:1-9) And thus, regardless of the inescapable problems with false seekers, all such men are to be examined by that which is affirmed to be infallible, as the noble Bereans exampled, and which use of authority the Lord and His apostles validated.
Nor does discerning what is inspired of God, or ratifying what others have affirmed, confer authority, else we should all be Jews, and even demons recognize who the true God is. God operates by demonstrating who and what is His, and and those who follow Him are evidenced to be doing so by their conformity to that which was already established, and according to the principle of Jn. 8:31,32, it is these who recognize the totality of what is Truth. And functionally these operate within the one true universal church, built upon the essential faith which Peter confessed, manifest in visible organic bodies.
In contrast are those who rest upon pedigree, (Jn. 8:33 and Mt. 3:9) and those who presume to a position whereby they alone are the supreme authority, and teach for doctrines the commandments of men. Such shall be abased in the end.