And herein lies Dan Luu's fundamental misconception: that universities see themselves as places where students come to learn skills, i.e. as places of certification producing skilled workers for industry. Most universities see themselves as academic places of learning for the pursuit of knowledge for knowledge's sake, which only incidentally graduates people whom industry happens to find their knowledge at least somewhat useful. If the university professor never needed to debug, use version control, or write clean designs in order to succeed in academia - why should he consider it worthy of being taught? If the university professor never benefitted from remedial review on his academic path towards becoming a professor, why should he consider it worth his time? Of course he's going to dismiss the notion to the tone of "some people just can't hack it in engineering." It's academic survival bias.
People talk about the STEM pipeline like some kind of demigod figure designed it from on high specifically with the intent of producing skilled technical workers, albeit with various flaws related to sexism and skill relevance etc. Of course, this is a ridiculous way of looking at the STEM pipeline, so it shouldn't surprise anyone that different actors in the pipeline have contrary motivations.