No, I'm not claiming that anthropologists are the "natural and proper authorities charged with gatekeeping"; that's nonsense. What I'm claiming is that the description of cargo cults that everyone knows is fiction.
Anthropologists who take "cargo cult" seriously have let themselves be trolled by pop culture.
It's a bit like saying that Christianity involves handling rattlesnakes and putting nails through your hands in the belief that God will turn your fillings to gold. That kind of misses the point.
1. Foreigners visit island, riding on flying machines, bearing mysterious technology and products.
2. Foreigners disappear.
3. Locals worship foreigners as gods, develop a legend that foreigners will return, and use ad hoc hand-made objects whose shape resembles foreigners' technology to summon them, such as model airplanes made of bamboo, or pretend radios.
It might all be based on a single anecdote, and that is obvious to anyone with two brain cells. There might have been as few as one actual "cargo cult". I don't suspect anyone believes there were anywhere near half a dozen of these, let alone tens or a hundred or more.
A single anecdote is enough for a working metaphor.
The Great Hanoi Rat Massacre was one particular episode in history, in one place in the world. Yet we can bring up that name in any situation where the wrong incentives backfire.
"Byzantine generals", anyone?