There's absolutely nothing wrong with using black boxes, and I'm not arguing that it should be totally avoided. I'm arguing that a lack of understanding of how to solve your problem leads to only gluing black boxes together as you lack the understanding with which to make more nuanced decisions, and to solve any part of the problems you have yourself.
It's also not necessarily required that you understand all of what you're doing down to the logic gates, but if you don't (to crib your example) understand some of what docx parsing may entail, or can't actually write any sort function (nor understand how to compare them), you're stuck with black boxes at even the highest levels, and then you're very likely to be exposed to the article's defined fatigue as you continually jump to whatever looks shiniest, lacking the understanding with which to properly compare your options.
It's also not necessarily required that you understand all of what you're doing down to the logic gates, but if you don't (to crib your example) understand some of what docx parsing may entail, or can't actually write any sort function (nor understand how to compare them), you're stuck with black boxes at even the highest levels, and then you're very likely to be exposed to the article's defined fatigue as you continually jump to whatever looks shiniest, lacking the understanding with which to properly compare your options.