I am thinking back when they named the protocol the HyperText Transport Protocol and the primary format the HyperText Markup Language, text was indeed the heart and soul of the medium.
At one point, images weren't even displayed inline but via a helper app. This is why Mosaic was a big deal.
HTTP has become a generic TCP wrapper for the common request->response pattern.
9792 42.750939000 74.125.109.232 10.1.1.21 TCP 1506 [TCP segment of a reassembled PDU]
RTMPT is RTMP over HTTP, but Youtube doesn't use it.
Yes, I'm being pedantic and annyoing.
I'll grant you that YouTube has a lot of cat videos, which probably doesn't have words in it. But those vlogs have a hell of a lot of words in them too.
---
A lot of video is streamed with RTMP, yes, but a lot of Netflix and YouTube content is available over HTTP now too (albeit in the contrived manner of chopping videos up into dozens of tiny files).
What the author extols in word is something quite effectively conveyed in many forms of art. Just as there is great beauty in the text of Baudelaire, there is incredible emotive power in koyaanisqatsi.
We should accept the author's challenge to behave with more conviction and purpose, to express ourselves in a more meaningful way. But to do so in word alone is too restrictive for the imagination to bear.
It is adapted from a Stephen King novel, having read it I can tell you you feel just as much.