Yet, the epistles to the Corinthians was written by St. Paul, and so were the epistles to Timothy and Titus. All lay foundation for such hierarchy.
Generally, the Church responded to challenges as it faced them. Among 12 men there is little need for hierarchy. As the Chruch grew, naturally it developed structures appropriate for its size.
I agree the hierarchal structure emerged in response to perceived threats. The distinction is that this particular system was not mandated by the Apostles. We have no examples of Apostles appointing successors, or Bishops, and proclaiming that they have unique authority and power. So if you wish to argue that the leadership system that developed was of divine intervention that's an interesting topic, but you really can't claim that the leadership system was set up by the Apostles themselves.