1. The men all dying at the same time without a sound is not natural. People will die of thirst or exposure one at a time, depending on their physical wellness.
2. The spirits of the sailors arising an working the ship is not reality. Even if one believes in spirits, spirits would not be able to grasp ropes or the wheel to control the ship.
3. The ghost ship moving at a tremendous speed toward the ship is an impossibility. The sails were full of holes, and the mariner's ship was not moving. There was no wind and not from that direction either.
4. The ship moving at such a speed that the mariner faints is also not possible. No ship can move that fast unless it was jet powered.
5. Returning to his home port with no crew, no navigation, no food is unlikely. Even with spirits guiding the vessel, they would have little control over it.
These supernatural events were supposed to tell the reader that a divine influence was in control, not the natural world.