[zaroth]

What do you mean “gets a distinct category”? Nutritionally it’s certainly possible to survive without eating fish, but a very large number of people do eat fish to survive.

Statisticians will collect and analyze data at many levels of granularity. Obviously it’s nice to know the types of food billions of people eat more generally than “fat”, “protein”, and “carbs”.

It stands to reason that fishing should be done sustainably, just like anything should be done sustainably, lest it become unsustainable. In other words, this says essentially nothing, right?

Only in the context of what the substitute is, how readily available it is, how comparable in cost, how comparable in nutrition, how much is it preferred or disliked compared to the status quo, and what negative externalities might exist in scaling up the alternative, only in that context can a useful discussion be had.