Who said this was a self-help article? The title is what it says. It's an interesting story that people found inspirational / fun to read. And sure, to use you

Who said this was a self-help article? The title is what it says. It's an interesting story that people found inspirational / fun to read. And sure, to use your words, it was self-promotion. But why is that bad? Regardless of your opinion of them as people, Steve Jobs did "shameless" promotion of iPhones, and Donald Trump did so with his brand. And if people found the information valuable, that's all that matters! Not sure where your preconception that this must be a self-help article is coming from.