I'm not saying it's all bad. Digital augmentation can be handy (love the hell out of document search), but honestly their examples aren't compelling.

I think accessibility is a major issue, where the text doesn't make as much sense without the interactive bits, and often the text itself isn't substantial enough to be stand alone.

But also, it's starting to cross the line between web app and document. I can print out a pdf and I just lose peripheral QoL benefits like document search. However, if I try to print a web app I usually lose a lot of the content/context.

Edit: as far as supplemental material goes, I'm all for it. People learn differently, so video, audio, web app, whatever are all great supplemental materials, but a good document should be able to stand by itself.