> Interestingly, videos don't seem to count? It must be a written description?

Wondering the same myself. Googeling for this issue turns up this power-point [1] which seems to imply on page 6 that "electronic publications, on-line databases, websites, or Internet publications" are also considered as "printed documents". But this is just a power-point so who knows which standard gets applied in practice.

I get the impression that the "printed document" language got written before digital documents and the internet were a thing.

I am not a laywer, don't know a thing about the topic, this is not legal advice etc.

[1] https://www.uspto.gov/sites/default/files/documents/May%20In...