You are talking about not an instance, but one singular individual who argued against the adoption of firearms, and not because they wanted to stay "primitive," but because they would have to entirely change their tactics. By the mid-late 20th century, firearms were much more common among the Zulu and the Zulu were very much interested in defending themselves against Boer settler incursions. This example is still instructive, however, as the firearms that were traded to the Zulu (in exchange for mining labor) were obsolete and difficult to maintain compared to the firearms their colonizing opponents were using. So you are correct, there was a difference in technology which granted the Boers and the British an advantage, at least in their task of efficient killing.
But what was the historical
context of this technological difference? As the above indicates, the late nineteenth and early twentieth centuries in South Africa were periods of rapacious and genocidal settler colonialism and appropriation, especially after the discovery of diamond deposits. It was also, not coincidentally, when the notion that Africans were more "primitive," and in fact, incapable by themselves of "advancement" along European lines was taken as common sense (that was taken as a universal goal of "civilization"). The conception of the Civilized/Advanced and the Savage/Primitive suffused all of these interactions with the Zulu. Versions of these concepts were developed and advanced by leading scientists of the day, and they were ubiquitous in European and American popular culture (including, in many cases, the pulp fiction that inspired dnd (see Haggard and others)). "Primitive" was the logic of "In Darkest Africa," and gave rise to the notion that "Civilizing" Africa was a European duty and birthright.
Famously,
Joseph Chamberlain:
The level of violence (between European colonizers as well) is what led to the creation of the modern concentration camp, as a type of wartime space and technology. South Africa, as is well known, retained the racial categories of the nineteenth century into most of the twentieth through the totalitarian and oppressive system of Apartheid.
I appreciate that you'd like to filter out all of this history in order to retain use of a word in your fantasy wargame (even though it is ironic that you choose perhaps the least felicitous historical example for this purpose). And that, you don't care if all of that history, encoded as always in language, matters to a POC writer and POC readers, because you want to defend an established white editor who works for a large corporation in inserting that word without asking the writer or considering its implications (and in a product attempting to highlight the company's willingness to hire a diverse set of writers). In fact, not only do you not care, you seem offended that anyone else would care, thus your comments in this thread.