I'm not feeling attacked, your response was confusing.
You used the term "conventional wisdom" when perhaps you meant "What I think other people believe, or I have read other people to believe." That was confusing because I don't agree with the statement you made in #1. Folks I knew at college, and since then, all shared a common experience when their natural ability completely failed them in college. They 'hit the wall' as it were. That was part of the maturation process.
My comment was that college was the perhaps the first time someone gets to choose to take on a multi-year task that is nominally difficult. That isn't a subjective statement, it is a descriptive one. I say perhaps because it isn't the only possibility but it was the relevant one because the original article is about college and more specifically college degrees.
Your second statement asserts a filtration process. Again, not mentioned by me, but implied in the original article because the plan to make up a degree (presumably to qualify). Except that it isn't a filtration process its a selection process. Lots of people work in this industry and others without any degree or other certification. They experience selection bias when they are in a selection pool of individuals that have degrees but that selection bias is a primarily content based. The same person would have no selection bias in a pool of individuals with degrees outside the area of the job.
Successfully completed coursework in a topic, not necessarily a degree, carries with it an indication of interest. I've got 12 college hours of CNC machining coursework on my transcript, that comes from being interested in manufacturing. Interested enough to voluntarily invest some of my time to learn more about it. It is a social signal of sorts that it stronger than just a conversational opening of "Yeah I'm interested in CNC manufacturing machines."
I also disagree with your #3 but I understand what your are saying. Anyone who came through college and didn't get an appreciation for what it tried to teach them (which is my interpretation of the statement 'treating it like a game') would in fact be a signal not to hire them. It would represent to me, a lack of maturation in their ability to evaluate the use of their time. In my experience, that lack of maturity expresses as poor judgement in the workplace.