Most of the "educational" and documentation style content there is usually "just" gathered together from other sources, occasionally with links back to the original sources in the descriptions.
I'm not trying to be dismissive of the platform, it's just inherently catered towards summarizing results for entertainment, not for clarity or correctness.
Still doesn’t make them a primary source. A good research agent should be able to jump off the video to a good source.
Some videos are a great source of information; many are the opposite. If AI can't tell the difference (and it can't) then it shouldn't be using them as sources or suggesting them for further study.
In that context, I think excluding YouTube as a source makes sense; not because YT has no useful content, but because it has no way of determining useful content.
I think that's the wrong metric for evaluating videos.
The investigation into Honey’s shenanigans[0] was investigated and presented first on YouTube (to the best of my knowledge). The fraud in Minnesota was also broken by a YouTuber who just testified to Congress[1]. There are people doing original work on there, you just have to end up in an algorithm that surfaces it… or seek it out.
In other cases people are presenting stuff I wouldn’t otherwise know about, and getting access to see it at levels I wouldn’t otherwise be able to see, like Cleo Abram’s[0] latest video about LIGO[1]. Yes, it’s a mostly entertaining overview of what’s going on, not a white paper on the equipment, but this is probably more in depth than what a science program on TV in the 80s or 90s would have been… at least on par.
There are also full class lectures, which people can access without being enrolled in a school. While YouTube isn’t the original source, it is still shared in full, not summarized or changed for entertainment purposes.
[0] https://youtu.be/vc4yL3YTwWk (part 1 of 3)
[1] https://youtu.be/vmOqH9BzKIY
Very few people manage high quality verbal information delivery, because it requires a lot of prep work and performance skills. Many of my university lectures were worse than simply reading the notes.
Furthermore, video is persuasive through the power of the voice. This is not good if you're trying to check it for accuracy.
e.g. this was very useful when I recently clogged the hot-end of my 3d printer. Quick scan with LLM, ask quote, Cmd-F in Youtube Transcript, then click on timestamp and watch. `yt-dlp` can download the transcript and you can put prospective videos into this machine to identify ones that matter.
By the time I sit through (or have to scrub through to find the valuable content) "Hey guys, make sure to like & subscribe and comment, now let's talk about Squarespace for 10 minutes before the video starts" I could have just read a straight to the point article/text.
Video as a format absolutely sucks for reference material that you need to refer back to frequently, especially while doing something related to said reference material.
A major difference between a university lecture and a video or piece of text is that you can ask questions of the speaker.
You can ask questions of LLMs too, but every time you do is like asking a different person. Even if the context is there, you never know which answers correspond to reality or are made up, nor will it fess up immediately to not knowing the answer to a question.
Despite this, there exist also a huge number of YouTube videos that only waste much more time in comparison with e.g. a HTML Web page, without providing any useful addition.
Or to put it another way, if you were building a Lego set, would you rather follow the direction book, or follow along with a video? I fully acknowledge video is better for some things (try explaining weight lifting in text, for example, it's not easy), but a lot of Youtube is covering gaps in documentation we used to have in abundance.