I think this article is conflating all fish and measuring them against a specific type of land animals.

Just like on land, there’s a big difference in sustainability depending on the type of fish you are consuming. Measuring a salmon vs chicken isn’t really an academically honest measurement. When looking at salmon, which takes a long time to mature. We should be comparing it to something more like beef, which also takes more time and resources to manage.

When comparing something like a chicken which takes a relatively low amount of time and resources to produce. We should be comparing it to something unlike Mackerel, which are significantly more sustainable and less resource intensive compared to salmon.