There's a further argument being made here that being literate changes the way you'd interpret and understand a YouTube video as you absorbed that information.

To be fair, author's point is more nuanced than "kids these days". He traces an evolution from: (i) an overly conservative but reality-based oral culture, to: (ii) a reality-detached and turbulent text-based culture, capable of envisioning our current technological era, back to (iii) another overly conservative oral culture. To me, the perceived threat seems to be how this second oral culture won't be based on direct experience of the real world, but on other people's (and AI's) interpretations of the former: taking the worst parts of both previous cultures (i.e. you can't think outside the box, and your box isn't even real).