The thing is, other than the professions (law, medicine, engineering etc) degrees weren't supposed to be vocational training for a specific job/career. That's what school, apprenticeships, polytechnics and adult education classes were for. Plus employers expected to train their junior hires, they didn't expect them to take specialised courses at their own expense before they would be considered employable.
Degrees were supposed to be academic, and it genuinely didn't really matter what you were studying because the value was in the skills you learned to be able to study a topic at that depth - research, critical thinking, ability to organise your thoughts into papers and reports, ability to debate and discuss, and so on.
But somewhere along the line it turned into the idea that a degree is "school+" , an add-on of specialist education to fit you to a certain job.
So I do agree with this "the skills they gained as students for 3 years could be surpassed by the skills gained from working doing many things for those same 3 years" but I don't agree that we should be making degrees more relevent to specific jobs, firstly because I don't think it's up to individuals to take on debt to fund the specialist training for an industry, and secondly because that means the courses will always be behind the current need anyway.