Good point, Schnell.
But the canon was not set in order to create a library of books from which to create a standard of religious doctrine. One might say, according to Jewish theology, that God did in fact inspire the Book of Enoch. The reason it didn't "make the cut" has nothing to do with that. Remember, the idea of a canon was invented by a heretic, Marcion. The whole reason there is canonization goes back to his heresy and what he was saying.
Marcion set a "rule" or standard for what was salvific revelation from the divine. Marcion said it was limited to what was written in his collection of books, whereas the Church said it was found in the Person of Jesus Christ.
The Church claimed that revelation was also found in what was written in the Hebrew Scriptures, yes, but ultimately in Jesus was the Word of God in human form. Revelation was also found in the providential leadings of the Holy Spirit that guided the Apostles and the faith of the Church as a whole. This was a battle over what was revelation from God and what was not, not whether God was inspiring certain books.
Marcion's KANON or "rule"/"standard" was that salvific revelation had: 1.) to be limited to a written format, 2.) claim Jesus was divine, 3.) reject and transplant Jesus as a divinity superior to YHVH, 4.) to be filled with hidden Gnosis ("knowledge") that could only be deciphered by the "select" chosen by the divine, but others could be saved to if they believed what the chosen taught.
The Church set a standard in contrast: 1.) that salvation was not limited to a "select" or "chosen" group, but was universal (KATHOLICOS, from which we get the word "catholic"), 2.) that any inspired texts written by Christians supported the catholic view that Jesus was the ultimate form of revelation, 3.) that the texts were but a continuation of the revelation given to the children of Israel, 4.) that the Christian texts were Apostolic (or written under the auspice of such), 5.) and that the texts were used in the liturgy (the liturgy was a Tradition believed to be inspired of God from the time of the Jewish Temple era).
Enoch was not widely read (if at all) in Christian liturgy, one of the requirements for determining what texts could be considered part of the revelation that included Jesus. There were no phones, computers, etc., from which the bishops could contact others and ask: "Hey, what are you adding in your Eucharist services after you read from the Torah and the Prophets?" It would take 200 years for the Church to gather all that information, not to mention then determine if the book was written under the auspice of Apostolic authority (another necessity). The Book of Enoch may have been inspired by God (which is why it appeared in some Christian collections), but it was not Apostolic. The canon of the New Testament was set with the event of Athanasius' Easter Letter of 367 CE.
The Jehovah's Witnesses have an odd view of the expression "inspired." They believe it is limited to direct revelation from God in written form. Judaism and Christianity believes inspiration refers to the providence of God, and it can happen to anyone. God can even inspire someone who doesn't believe in God to do something, according to this understanding. So even if Enoch is inspired, the fact that it didn't measure up to the other standards is why it was not included.
You might have already noted that Jehovah's Witnesses tend to reflect the Marcion heresy: they believe that God has "hidden knowledge" in the Scriptures; they believe holy writ is the ultimate form of revelation from God (if it's not in the Bible, it's not truth); they believe only a "select group" are given insight into the hidden truths of Scripture; they believe (like Marcion) that people have to follow the select/chosen ones in order to saved. None of this is taught by Christianity or Judaism.
The term "canon" is Greek, and no such concept was ever thought of in Judaism until relatively modern times. The Masoretic text became the standard for the Jewish text even though there are early traditions which are still extant. With the Council of Trent, the Church stated that the books of the Alexandrian Septuagint were also part of the "canon" (thus the reason for the Deuterocanonical books), but prior to this there was no formally declared "canon" of the Hebrew text even in Christianity. (These so-called "extra" books remained even in Protestant Bibles until 1825 when the British and Foreign Bible Society were the first to remove them from their distribution copies of Scriptures due to pressure from the Puritans and Presbyterians in their midst).
Now, if we were to rely on a "canon" made up of what was popular, the New Testament would have looked a bit differently. We would have had the Shepherd of Hermas and the Apocalypse of Peter. The Wisdom of Solomon and Ben Sira would be in the New Testament instead of the Catholic Old Testament collection of "extra books." There would be no Revelation to John, and probably no 2 Peter. The canons of Christianity have nothing to do with who was quoting what but what Church Tradition said was canon. Those who follow accept the canon are actually following Catholic Tradition, even those who claim they believe in "Scripture alone."
As a Jew I find that very, very funny, especially when a Jehovah's Witness comes to my door and says they believe the Bible is inspired but not Catholic Tradition.