His main complaint seems to be that he couldn't teach kids how to interact with a file system. I don't think the concept of a file system is an easy one to gras

His main complaint seems to be that he couldn't teach kids how to interact with a file system. I don't think the concept of a file system is an easy one to grasp. And it's not something we should be expecting schools to teach. I once had the privilege of doing the converse, teaching an 80 year old woman the same concepts. I had exactly the same problems he described. These things are not simple nor intuitive, nor are they really needed for basic usage of a computer. I taught them to her because that was what my formative years using computers was like, and because that is how you understand what's going on under the hood. But I had to quickly roll back my ambitions to non-CLI interfaces because she just didn't have the same kind of time I had when I was 13 to just spend hours and hours figuring it all out. It's not necessary to learn how to touch type, and it's not necessary to learn the file system concepts used by the userland. You can do amazing work with a computer without that knowledge. Pedagogy doesn't just involve knowing how to teach, but also in knowing what needs to be taught. You don't need to dive into the intimate details of radiocarbon dating to get kids excited about dinosaurs.