Some black people buy guns for self defense. Some black people buy guns as insurance against tyranny. Some black people buy guns for sporting purposes. The list goes on and on. All gun buyers have different motivations.
Even if I were to assume your assertion is correct ("...Guns seem to make them less safe on every level"), not everyone (which includes people of all races) rates "safety" as high on the priority list as you evidently do. Personally, I like the fact that carrying a gun gives me more options than I would otherwise have. Do those options make me less or more safe? Don't know, and don't much care; I'll take "more options" over "less options" any day in the matter of self defense.
Your opinion noted. As I mentioned earlier, the NRA is pretty responsive to the wishes of their millions of members, who, through voting, set the direction of the organization. As a member, I personally don't have a problem with NRA focusing on RKBA instead of 5A. My practice is to support the 5A by donating to the ACLU. They do a pretty good job of it, considering how small they are.
I already mentioned some of the reasons black people buy guns. I suspect that most people who buy guns don't even consider Fox News, the NRA, or police malfeasance when they are making their purchase decision. Of course, if these things are important to you, you probably shouldn't buy one.