Actually NY and NJ harbors are kinda special in that there's a giant continental shelf offshore with all the wrecks on it. And its outside the vessel traffic lanes (VTS). West Coast wrecks are generally within the VTS. So in NY and NJ large vessels are on their own navigation wise and yes you can get run down. In comparison for instance, inside of the Channel Islands to Long Beach CA, the entirety of Puget Sound and the Salish Sea from Comox BC south are all under the direction of the US and Canadian Coast guards and ships have to follow established lanes and get authorized to start, stop, enter, and leave those lanes. You can't just dive in those lanes and if you do get permission to dive there they will route traffic around you for the duration of your dive.