That is the staple claims of American generosity and exceptionalism. You forgot the Marshall Plan though.
You are right that there are more people claiming Norwegian ancestry in the US then there are people in Norway. They are proud of it to.
They eat Lutefisk, Lefse and Brunost in large quantities, thus contributing to the trade balance between the US and Norway.
You are also right that Kjell Inge Roekke made his initial fortune in the US. He introduced modern fishing methods and on board processing to the US fishing industry. He is still contributing to US shipbuilding as the defacto owner of the Philly Yard, introducing modern methods there to.
His Aker Solutions are a major operator in the GoM subsea equipment and construction industry, using many US flag vessels, but also some others when no suitable US flag vessels are available, or able to handle the task.
But that has nothing to do with the UNCLOS or OCS, which is the subject here. The UNCLOS give US the right to claim exclusive rights (EEZ)even outside the OCS, up to 200 n.miles offshore.
It also open up to extend that claim if the OCS extend past that limit, which the US would love to do in the Arctic, but is stopped from doing so since it has not ratified the UNCLOS. Russia is making such claim in the Arctic, as does Denmark on behalf of Greenland.
Australia has claimed extended OCS in the Timor Sea, thus many of the large Gas fields there are within Australian EEZ, although closer to Timor Leste. (David and Goliath?)
In the GoM area the only possible conflict over the OCS would be with Cuba or Mexico. I'm not sure if there are any counter claim, or if the various EEZs are defined and agreed according to the median line principle, as is normal.
In short, ratifying the UNCLOS would be to the advantage of the US and not loosing "sovereignty" of the OCS, which you cannot claim anyhow. (Only territorial waters are "sovereign")