Still, the business as it's presented is destined to fail unless they have a broader-based pivot in the works.
It's not that you are racist, and I didn't say you were. However, the reason you don't understand that "natural hair" is a unique identity within the African-American community speaks to your lack of experience, and that lack of experience probably has something to do with the culture you come from. That doesn't make you racist, that makes you ignorant, which is fine as long as you don't assert that your ignorance is more correct that statistics that contradict you.
This is why it matters that diverse people build businesses: there are people out there who's needs I couldn't predict because I don't have the experience to know what they are. It is incredibly arrogant, however, to assume that because something isn't a part of your personal experience it either doesn't exist, doesn't matter or is doomed to failure.
Natural hair is political in a way your examples aren't. In fact, your reaction is a perfect example of what the original article is talking about: people projecting their own experiences onto the rest of the world and thus making wrong assumptions about what will succeed or fail. In this case, those assumptions are both gendered and racial in nature: this is a profitable start up that most white men would never have thought to create.