I am talking about the complement of the plot.
I am saying that every student should be doing these tasks. The students without these skills should be learning them too.
Then no one is being taken advantage of. Then all of the students are more marketable. These skills are useful to academics too: successful junior faculty will one day need to stand up their own labs with their technical skills.
This isn't about skills development. It's about using people who already have these skills as engineering support labor for the research group while paying then 1/2 to 1/5th of what they'd make in industry doing equivalent work (that, again, they already know how to do!)