Also Jones Act: ships from Asia can't pick up cargo from Hawaii on the way and drop it in mainland US. This means that shipping between Hawaii and mainland is much more expensive then it needs to be.
https://www.grassrootinstitute.org/wp-content/uploads/2020/0...
Also the OP suggested that Hawaiian production is on decline so shipping from Hawaii to mainland is the issue.
However, the Jones act doesn't really have much of an impact compared to the significantly higher cost of labor in the US compared to brazil and india. Also the US got rid of alot of sugar subsidies, and import controls which essentially made sugar growing aside for some specialized situations infeasible.
Jones Act doesn't accomplish what it's supposed to do but that's mainly because it was weak protectionism. Many other countries just shovel government money into their shipbuilding at rates that would probably make many just as angry.
It doesn't help that the US is full of non-contiguous territory separated by deep ocean. Other countries have similar laws but aren't as impacted.