Upskilling is one of the most ineffective costly ways to try and "re-program" workers and it mostly doesn't work because it's not about skills it's about talent.
Engineering is a talent skill there is a world of difference between teaching someone starting from scratch and then starting someone first having to unlearn what they learned to then learn perhaps a completely new way of thinking.
Most of the reskill programs I have heard of failed miserably exactly because the skill isn't enough.
I sort of agree in that orgs can't simply create massive education programs to re-purpose skill-sets/talent. That might have been possible "back in the day" before project managers were breathing down people's necks, but not today.
But the brightside is that talented people will find a way to "upskill" themselves in whatever environment they find themselves in. It is then up to the candidates to sell themselves and for the potential employers to be flexible about considering different backgrounds and nurturing the development of cross-functional skills that are needed for so-called data-engineers.
The skills listed in the article are all fairly common but its hard to find enough of these skills within individuals. For example, its not hard to find folks who can do the care and feeding of sql-server databases, or skilled programmers, or analysts who understand the business domain intimately. The problem is getting all of these together in one individual in a "know-enough-to-be-dangerous" level.
That's not always the case. Talent doesn't exist in a vacuum.
Someone with a natural talent for picking up new development skills will still learn data engineering far faster when provided with proper resources and strong internal mentorship.
I can see how you might make this observation after observing a poorly conducted training program.
The problem is that there aren't that many people with natural talents. They exist but it's very hard to sync them up with where demand is.
Also this is not just one poorly conducted training program. Denmark spent billions up-skilling parts of their work force. The results where simply no there. Something like 6 out of every 1000 person or something like that.
I am a believer in inherent talent but Data Engineering is a skill set.