i think this request is talking about putting media – video, audio, sounds – inline into the text of comments and notes and such. right now, you can add images using html or markup, but you can’t just paste an image into the text of the comment or notes. for sounds and video, you can’t even add them using html.
i don’t think this request is talking about actually adding video as one of the types of evidence that can go into an observation. (there is a separate feature request for adding video as evidence: https://forum.inaturalist.org/t/upload-videos/5426 .)