Most successful fish name change from a marketing POV was rebranding Patagonian Toothfish as Chilean Sea Bass. BTW, they are incredibly UGLY and look nothing like sea bass.
Dolphin (fish) became Mahi Mahi...............
Monkfish is ugly too, but it’s known as poor man’s lobster.
IIRC, carp caught from clean water is as good as other species. In eastern Europe carp are fattened in holding tanks & served as a holiday meal.
What about the Asian snakehead invasion? Chinese say the best thing to do about them is use plenty of ginger when you cook ‘em
And I still believe that “scallops” are shark plugs. Shark was once marketed as `grayfish’ and `steakfish’. Put `shark’ on the menu & people think of Jaws & belt buckles.
Dolphin fish became mahi-mahi only because nobody wanted to eat Flipper.
;^)