It sounds like the US does pay attention to sunken ships with substantial amounts onboard near US shores, and has removed oil before, but also, sounds like this is the government being concerned about the spill potential rather than companies with interest in valuable salvage:
Oil to be Removed from Sunken WWII Tanker near Long Island
The Coimbra is one of 87 wrecks prioritized for oil pollution risk in a 2010 NOAA study — a continuation of the Remediation of Underwater Legacy Environmental Threats (RULET) project, a joint effort with the Coast Guard to address threats from vessels sunk off U.S. shores that contain significant volumes of oil. After looking into about 20,000 known shipwrecks, the two agencies identified the 87 high level risk wrecks. Those sites are routinely monitored by the NOAA Satellite and Information Service Satellite Analysis Branch.
I suppose that dealing with sunken vessels without salvage potential probably isn’t super-high on anyone’s priority list.
Periodically on British and European forums, I’ve seen discussion about a sunken WW2 ammunition ship at the mouth of the Thames; an explosion would cause a lot of damage to buildings near the shore. The Brits have a fair amount of money, the thing is not in a great place, and the wreck is in shallow water, with the ships masts above water, so accessible, and they still haven’t removed it.