Good point and very true.
Rather, the Church was what decided canon -- you can correctly say that the "major" books like the Gospels, most Epistles etc were already decided and that is true, but there were other canons -- as I pointed out, the canon was not "well known" in its entirety before "any Council said anything" -- note "in its entirety" -- there were canons created like Marcions which just included 10 Pauline Epistles, the Gospel of Luke (rather an edited version called the Gospel of Marcion) in 140 AD -- but you and I wouldn't accept that canon today
Though the Pauline Epistles were circulating freely, not all were considered scripture by all. The Gospels on the other hand were pretty unanimously accepted.
The next "canon" was Origen's which had all the books which we have now except for James, 2 Peter, 2 John and 3 John and it had the Shepherd of Hermas as scripture.
In fact in the first few centuries there were disputes about the letter to the Hebrews as well
only in council was canon closed -- the councils were inspired by the Holy Spirit to do so.