I don't get it

I don't understand how nicknaming someone Barracuda is supposed to be a compliment.

This website says:

The great barracuda is an eating machine and it has the bulk to prove it.

While this one says:

In murky water, it tends to attack an object even before identifying it.

I don't find anything saying these fish are intelligent and of course they don't have a reputation for diplomacy or problem solving or any other skills that make up the tool chest we humans need in a leader.

Even in fiction they're not portrayed in a positive light. Look at Finding Nemo, all of Nemo's brothers and sisters were killed in the eggs by a barracuda, who also killed Nemo's mother, Coral.

I know we frequently get stuck with nicknames that are less than flattering but it's just weird to me that someone would embrace this one to the point of pirating a song by the same name. Color me baffled.