I also listen religiously to Cortex, so I think have a good sense of what can go into the writing. And yet his videos, while certainly entertaining enough, only sometimes go reach a depth and quality that I think is possible in video. His visual style is exactly the unprofessional style KB describes - stick figures, simple shapes in what is essentially a Powerpoint presentation. Video can be so much more than just a script with something to keep your eyes occupied with.
Edit: and yeah, once in a while I come back to the idea of making veenspace YouTube videos. :)