This seems, at best, an anecdotal and/or an arbitrary distinction about what qualifies as "Engineering". Software engineering, as an applied discipline both in name and in practice, has existed since at least the mid-to-late 1960's. And many of the orgs in those days which adopted that title normatively, employed many folks who were "focused and trained in their skills" (e.g. NASA) and worked alongside of those in the more classical engineering domains.
Speaking in my own experience, working closely with hardware/mechanical/electrical folks on a novel product line, they are exposed to a lot of the same subject matter covered in the article. Many of the tradeoffs explored there are absolutely relevant to the older engineering disciplines.
