At the start, the goal of teaching is to produce highly-skilled graduates who can contribute greatly to the task at hand. During that phase, there's no problem with a high drop-out rate, and no need to "sell" the discipline by extending its reach. This is basically an exponential phase.
Later on, as faculty slots fill up, a steady state can be reached, in which the supply of graduates meets the demands of the community. That's when things get extended, and the goal can start to shift from turning out highly-skilled graduates with narrow focus to simply educating. Every university has a psychology department that has huge classes. Students in those thousand-seat classes are not going on to become psychologists; they are enriching their experience of life. And the dividing line between what they are learning and what they could learn in grade 10 is very thin, so this kind of material can also be taught in high school. Again, those 15-year olds are not destined to work in psychology, any more than they are destined to work in history, literature, or all the other fascinating courses that are being offered to them.
It looks as though the author is suggesting that education in computing is entering this state, in which there is very little probability of the student becoming a professional. And, in that scenario, I agree fully with the theses of the article.
But I still think there is a place for the old system of teaching a language and expecting that some of the students will go on to contribute at the cutting edge. It's great to have classes on photoshop and the like, but there is a question about what they ought to be called. Perhaps CA (computer applications) is a better acronym than CS for that student in sixth grade.
Using the same title for everything that happens to involve using computers is a mistake, not least because it gives students an incorrect impression of the pathways they might want to follow.