I've commented on this development before on HN, so I'm glad to see this post on the front page. From a few months back:

"...the fact of the matter is that kids getting into high tech and programming mostly don't read books anymore. How do I know? Recently I was hanging out with a bunch of high school students who asked me how I learned. I said it was mostly via books and man pages. "Yeah, don't sleep on high quality written material. O'Reilly. Wiley. Addison-Wesley. Manning. MIT. No Starch Press. &c...

"Well. You should have seen the look on their faces. I might as well have morphed into the Steve Buscemi meme "How do you do, fellow kids?" They looked at me like I was a total relic or greybeard and said things like "Nah, nobody reads tech books anymore; I learned Typescript from YouTube videos."