Reading Gödel, Escher, Bach? Intellectually positive. Reading a Harlequin novel? Intellectually neutral or negative (opportunity costs). The point is, as for intellectual advancement, choice of content is actually what matters, not the medium.
Regarding books vs video : If a book mentions a Wankel engine, I have to look up that definition or gloss over it, hoping it's concept is revealed later.
If I watch a video and it mentions a "Wankel engine" and I see an engine rotating around and immediately get the gist of how it works. E.g. https://www.youtube.com/watch?v=josJhz8VS8A
Regarding books vs video : If a book mentions a Wankel engine, I have to look up that definition or gloss over it, hoping it's concept is revealed later.
If I watch a video and it mentions a "Wankel engine" and I see an engine rotating around and immediately get the gist of how it works. E.g. https://www.youtube.com/watch?v=josJhz8VS8A