Very good points. Here’s another. The believers knew from the time they received the letters which ones were from Paul, which from Peter, which from John, etc. The Councils did not *establish* which letters and Gospels were authentic. Rather, they codified/officialized what was *already* known and accepted among the believers.
Now iirc, there was a genuine debate re James. However, the Holy Spirit oversaw that debate and ensured that it concluded with the right decision.
My Church History class was a long time ago. :)
True; but most of us STILL have the main textbook and use it from time to time to look things up that we've misremembered over the years.