Alternatively, rather than view all Stack Overflow questions as inevitable, we could view Stack Overflow as a failure of the core documentation or system to add

Alternatively, rather than view all Stack Overflow questions as inevitable, we could view Stack Overflow as a failure of the core documentation or system to address user issues sufficiently. And better documentation should result in fewer SO questions. In terms of the point of this article I think it is still in-line with what you are saying - as Stack Overflow answers are useful to solve an issue but are much harder to parse/read than properly written documentation on the same topic.