Dampier, Cape Lambert, Port Hedland, are all single jetty deep water ports with single high capacity conveyor belts that run out to human operated ship loaders.

These aren't high volume container ports with fancy networked container picking & stacking robots servicing multiple ships at a time with complex consignment lists.

The iron ore shore facalities are physically, electrically, network wise, isolated mostly manual operations with joystick loaders, captained pilot boats, and line of sight sea flag siognalling and radio channel communication.

You can take them out with a bomb but not a cyber attack.