From the article I doubt that this population was based on "plunder and exploitation". Apparently the scientists reconstructed their diet from skeletal remains

From the article I doubt that this population was based on "plunder and exploitation". Apparently the scientists reconstructed their diet from skeletal remains, and you'd expect your standard marauder types to feed more on meat, since meat packs more calories (and satisfaction) per kilo. The scientists say they didn't find many signs of violent deaths (in contrast to South American sites) and collapsed without signs of an exodus. Also the location of the island can't have been that convenient for seafarers of the period. On top of that, they didn't do much fishing at all, further pointing to a lack of maritime ambition.