No human knows how to solve global coordination, i.e. if some countries switch to be sustainable and some others don't, the former pay the costs, but the latter

No human knows how to solve global coordination, i.e. if some countries switch to be sustainable and some others don't, the former pay the costs, but the latter gain a signficant benefit as their immediate catches simply increase (as fish don't care about borders). We don't have a "world government" that can practically impose binding restrictions on anyone in cases that don't go so far as where military violence makes sense.