A massive amount of seafood in the US is intentionally mislabeled, which leads to a lot of problems because tilapia, for example, causes upset stomachs for a lot of people.
Meanwhile, tilapia is farmed. Hence misidentification there would be intentional.
For comparison, there are 8 species of salmon. We eat maybe two of them.
All of which are cichlids.
That's a long way away from "any whitefish".
"Whitefish" most commonly refers to cod and pollock, not tilapia.
And we eat every species of salmon, not just two.
tilapia are cichlids, and are not part of the old definition; not sure if the definition has changed