I did not say they were not divinely inspired. I said they were not instituted by God.
There is no point in making an idol of the institution. The institution of the church exists for one purpose only, and when it ceases to do that, it has lost it’s mandate.
The patriarchates, and I am including the bishop of Rome in that august collection, are not a separate order (there are the three higher orders of bishop, priest and deacon, that’s it), they are bishops.
Their offices exist essentially due to the human condition, human history. The Israelites needed a king, and they got Saul.
We need patriarchs, popes and catholicos.
But ultimately the authority in the church is the bishop, to work in concert with each other (and not at cross purposes) these gather into synods (for convenience the synods originally gathered according to their political provinces in the Roman empire, but other criteria were used outside of the empire) and the chair of the synod (not as the ruler, but the chair) is the Metropolitan, the bishop of the greatest city. This pattern repeated all over Christianity, not just a few times but dozens of times, perhaps hundreds of times, it is a principle of the organization.
Some Metropolitan churches carry a great deal of prestige because of their great age, because they were established in great cities by apostles (often martyrs for Christ) and developed larger, closely knit congregations. I think we can say that apostles often brought their closest associates, their disciples and “camp followers” with them as they traveled. We can assume that these founders. the apostles and their disciples, lent a special character to the churches where they stopped. There was a closer connection to Christ where there was so much orthodox learning and study abut Him concentrated in one place. These were the places to go for answers.
That made the bishops of those churches special to our eyes, and they were seen not just shepherds, but ‘great fathers’ (patriarchs/popes). That was our doing, we saw them as special, it was an evolution in our thinking, and that was reflected in the canons.