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.
How am I being racist? The idea of a black social network isn't 'bad', it's the fact that they're selling it as a network for a specific hair type. If their premise is code for 'a black woman's network' then they should explicitly say it. I'd invest in that, but not a curly hair network. Projecting some idea that I'm being racist in my analysis is ridiculous. They aren't getting 2 million uniques based on a hair style, there's obviously more to the business than hair.
Still, the business as it's presented is destined to fail unless they have a broader-based pivot in the works.
It isn't all "black women"; it is a specific demographic of black women. The same way hacker's news isn't a website for people with computers or Spotify isn't for everyone with ears.
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.
"Code" to you is "explicit" to the target demographic culture. I'd argue that you are not in that culture--and though I wouldn't say you're being racist (and actually looking back it's _you_ that used the word racist first!), I would say that your criticism is coming from outside the culture.
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.