A big gripe I have about youtube links: I can't learn anything about the video from the link. Once in a blue moon a youtube source is actually good. But the odds are so low that I often wont even bother clicking.
I completely ignore YouTube links, if they are secondary, or tertiary sources. (They can be pretty good as primary sources. If someone claims that an event happened, and then links to a YouTube video of that event, that citation is often quite conclusive as to the validity of that claim.)
They are unsearchable, unskimmable, and require way too long to get through. And if someone links them with a particular timestamp in mind, because some fifty-second segment is the salient part of the link, then, at best, they are an appeal to authority.
You can't maintain an asynchronous conversation with a youtube video in the middle.
With a link I can scan for support of your position and mine. With the video the conversation just stops for 20 minutes while I watch a stupid video. And then I can't cite anything from it unless I'm a transcriptionist.
YouTube links are automatic ignore for me. Video that isn't a sound byte or "here is that thing happening exactly" is a horrible way to consume information related to a discussion.
