It was a very interesting and well researched essay, congratulations. Whilst I agree with others who say that there's no reason to stop using the term cargo-cult, I did very much enjoy reading about the history of the phenomenon. Some of this I knew about already, like the frequency with which these tribes decide to destroy all their food and supplies in order to bring about prophecies of plenty, but a lot was new. I might have actually used one of the fake photos before in an essay of my own, for shame.

I think you're getting pushback for these reasons:

1. The times, they are a-changing. The title and conclusion of the article (whilst mild) are telling people not to use an otherwise useful phrase because it might be offensive to Micronesians.

2. Some of the conclusions seem on fragile ground honestly, despite how well researched they are. You start by claiming that Feynman misrepresented cargo cults because he watched a bad movie, but then give lots of examples of tribes doing the exact things he talked about. You even present photos of a "radio tower", mention a "radio" that was just a woman wrapped in wire and other such fake objects.

Feynmann's point was actually an important one about science, not Melanesian tribes. That was just a hook to get students to listen, just like how you used the famous physicist as a hook to get people to read your article. But I'm struggling to see where the inaccuracy is here. Given he spent only a few sentences on it, he did seem to correctly summarize what cargo cults are and the fact that some of them pre-date WW2 and talk about ships is really neither here nor there.

3. There is a strong overtone here of "European settlers were bad and wrong and cargo cults wouldn't exist if they hadn't turned up", which is unsupportable. These were people who started suffered a horrible prion disease because they engaged in cannibalism, something the nasty Europeans put a swift end to everywhere they took control. Their garbled belief systems about good stuff appearing when they get the rituals right weren't caused by Christianity, which is why they had to imagine that the Bibles they'd been given were incomplete to try and make it fit with their pre-existing ideas. In fact the Old Testament explicitly forbids exactly the kind of idolatry they were engaged in, leading to the interesting thought that maybe that rule evolved because it lends itself to self-destructive ritualism and cargo cult-like thinking. Christianity also forbids many other self-destructive ideas often found in isolated tribes, like human sacrifice and inter-tribal warring. If so it would seem like Christianity is the fix, not the cause.

4. The semantic drift in how people use the term seems small. Cargo cult programming doesn't work, that's the reason it's criticized. Given enough copy/pasting from Stack Overflow you might get something that superficially looks right, just like with enough work you can make an airport out of bamboo that looks right, but it won't actually meet its spec for functioning correctly because important stuff will be missing.

Whilst you certainly succeed in making the point that cargo cults were a more complex phenomenon than what Feynman presented in his brief intro, I didn't come away convinced that the metaphor is misused.