Show me in the 4 Gospels where Jesus defined a Canon? Lets see it. I know where you are going to, Luke 16:16 and Luke 24:44.
That does not define a Canon. There are books in the OT that do not even mention God by name [Esther and Song of Songs] but that does not mean they are not Sacred Scripture. But they don’t contain direct prophecies of Christ, yet they are inspired by God and part of the canon.
There are books of the OT never directly quoted or even alluded to in the NTJ which would include: Judges, Ruth, 2 Kings, Esther, Ezra, Nehemiah, Song of Songs, Ecclesiastes, Lamentations, Obadiah, Jonah, and Zephaniah.
Yet Christ is celebrating the festival of Lights [John 10:22] during the winter in Jerusalem which we read in both 1 Macc 4:36-59; 2 Macc 10: 1-8]. So 2 explanations, 1] Christ is affirming the canonicity of these books or 2] He is following Jewish Sacred Tradition.
Either way it doesn’t work for you protestants. As a Catholic, as well as Orthodox, Oriental Orthodox, and Assyrian Church of the East, it is canonical for all of us. It was also Canon for the largest number of Jews in the periods a few hundred years before Christ per the LXX [Septuagint]. The Pharisees [Palestinian canon] was the 38/39 book canon [Esthe?] the Sadducces only the Torah, same as Samaritans and the Qumran Jews had a canon similar to the Pharisees but seemed to also include Enoch and Jubilees which might be why the Epistle of Jude cites Enoch.
So to say there was 1 Jewish OT canon at the time of Christ is historically note true. There were at least 4 different OT canons.
Then you either accept that definition or you don't....and based on the remainder of your post you don't.
I'm going to stick with what He said.