(This post is not defending the original article, just discussing this specific comment.)
Having never read an HR for Dummies book, and as a pure technical interviewer, I still frequently ask this question. The point is to not think of it as an adversarial question, like I'm going to mark you off for a bad answer.
It's simply to know how you want your career to proceed. Do you want to be an expert at some specific part of the programming world, an experienced generalist (consultant?), an architect, a manager or product lead, start your own startup, ... ?
This is a very important question for you and your manager to be on the same page about. It helps your manager know how to motivate you and what kinds of work will excite you to move your career forward. And it helps you evaluate via small experiences whether your vision matches up with your skills and what you actually enjoy.