1. They have the technology to not only repel any invaders in the past, but to completely hide the existence of thier country. Why would they focus on making weapons at max efficiency at the cost of forsaking traditional standards for wide-scale combat when that isn't their policy to begin with?
2. This is a movie based on comic books, not a documentary on a prototypical futuristic African country devoid of the influences of Western culture. Of course aesthetic is going to be the focus. The internal logic of the style of the culture works, and thats what's more important. The spears and cloaks are fairly practical, are more advanced than the guns/armor the rest of the world have, and at a glance still appear to be the "primative" weapons of dirt farming Africans in an impoverished country which is lending to the idea that they are hiding from the world.
3. You still seem stuck on the idea that guns are an inherently modern or perfected design rather than realizing that the guns we have now are just the perfected design of a specific styling of a weapon developed in specific culture(cultures if you consider the Chinese fire-lance a primative "gun" although that design influenced early Europeans and the European musket and rifle largely replaced them in design and purpose). I don't mean to call you out on your biases in a way that implies you aren't "African enough" or any BS like that, but all of your arguments seem to condemn anything that looks too "stereotypically African" while treating anything not specifically African as both "more modern" and "advanced". Whether its condeming the use of the spear(which IS a traditionally African weapon even past the hunter-gatherer primative roots), or the aesthetic of Wakanda's architecture and clothing(which draw from African cultures and styles), or the way their governing system works(with the implication that their system is "barbaric" and that something closer to democracy or other Western governing systems is inherently more "advanced"), you can't seem to divorce yourself from the idea that there should be something else, something more Westernized to represent this imagined African nation, because what is shown, things that are inherently African but still common enough to be digestible to worldwide audiences is somehow lesser than what you define as "advanced". Hell, the fact that you are so hung up on disregarding tradition, regardless of what part of the continent you are from, is a distinctly "non-African" mindset and a bit telling on where your biases lie.
