This statement stands in direct contradiction to Scripture itself:
2 Timothy 3:16
All Scripture is inspired by God [literally: God-breathed] and profitable for teaching, for reproof, for correction, for training in righteousness;
I don't think those two sentences are contradictory in any way.
As you rightly point out, God "inspired" (ie breathed) the scriptures, which somehow got written down and compiled, with false scriptures being rejected. The original commenter believes that tradition was the mechanism for this process. You may think that there was some other process that did not involve tradition but that would not mean that the two sentences are contradictory, but just that you think the original commenter interprets it incorrectly.
Incidentally, I'm curious as to what you believe the process by which Christian scripture was reduced to writing and compiled was.
Also by the way, I think it's unfortunate that English uses the German-root verb "breathe" instead of the Latin root "respire" (whereas we use respiration for the noun form), because in ordinary speech we lose the beauty of the connection between inspiration and breath that you point out in your comment.
It would have been pointless for the Holy Spirit to inspire Scripture and then retreat to a passive, detached position to allow an errant and faulty process to take over. Either the Holy Spirit inspired AND preserved Scripture, or we can never be sure if what is in the Bible is the Word of God or the product of fallen man’s tradition.
Christian script-ure was not "reduced to writing," since it was not scripture unless it was written. And writing is God's chosen most-reliable means of long-term preservation. ( Exodus 17:14; 34:1,27; Deuteronomy 10:4; 17:18; 27:3; 31:24; Joshua 1:8; 2 Chronicles 34:15,18-19; Psalm 19:7-11; 119; John 20:31; Acts 17:11; Revelation 1:1; 20:12, 15; Matthew 4:5-7; 22:29; Luke 24:44,45; Acts 17:11)
And before there ever was a church that imagined it was essential for the laity to know which writings were of God, a substantial body of wholly Divinely inspired writings had been established as authoritative, to which the NT church appealed to.
Which establishment was essentially due to their enduring heavenly qualities and attestation, as was the case with men of God, even when rejected by the historical magisterium. It was the laity who held John the baptizer to be a prophet indeed, while those who sat in the seat of Moses did not, and thus rejected his baptism as being of God, and having authority. (Mark 11: 27-33) Likewise they rejected Christ and the church, which began in dissent from the historical magisterium, contrary to the Catholic model.
And inclusion in Scripture is how we know if something of oral transmission is the word of God, not by the uninspired words of popes and councils.
And as i abundantly evidenced , as written, Scripture became the transcendent supreme standard for obedience and testing and establishing truth claims as the wholly Divinely inspired and assured, Word of God. Thus the veracity of oral preaching subject to testing by Scripture, and not vice versa.
It was not because oral tradition preserved the Word of God that brought about a national revival, but because of the wholly inspired-of-God written word:
And Hilkiah answered and said to Shaphan the scribe, I have found the book of the law in the house of the Lord. And Hilkiah delivered the book to Shaphan. (2 Chronicles 34:15)
Then Shaphan the scribe told the king, saying, Hilkiah the priest hath given me a book. And Shaphan read it before the king. And it came to pass, when the king had heard the words of the law, that he rent his clothes. (2 Chronicles 34:18-19)
And the king went up into the house of the Lord, and all the men of Judah, and the inhabitants of Jerusalem, and the priests, and the Levites, and all the people, great and small: and he read in their ears all the words of the book of the covenant that was found in the house of the Lord. And the king stood in his place, and made a covenant before the Lord, to walk after the Lord, and to keep his commandments, and his testimonies, and his statutes, with all his heart, and with all his soul, to perform the words of the covenant which are written in this book. (2 Chronicles 34:30-31)