I would describe this kind of communication as lazy and not very good.
I personally think that if their meaning is getting through, it’s a perfectly fine mode of communication. Lazy, maybe, but there’s nothing inherently wrong with laziness, wanting to do more with less work is kind of a basic part of the human condition, it only presents a problem if it’s preventing something from getting done. If there is a meme or a short video or something that perfectly sums up what I’m trying to say, why shouldn’t I use that resource instead of trying to rephrase everything into my own words? This isn’t 10th grade English class, you’re not going to fail life for plagiarism because you linked someone to an existing Wikipedia article instead of trying to rewrite it yourself.
Now if their meaning isn’t coming through, that’s of course an issue, but not one that necessarily reflects poorly on them nor on you. People absorb information best in different ways, you’ve almost definitely heard about people having different learning styles, different types of intelligence, and of course everyone has their own life experiences and frame of reference. Different forms of communication will reach different people in different ways. To everyone absorbs meaning from written words well, not everyone can effectively put their thoughts into words, not everyone speaks meme fluently, different experiences can lead people to interpret something in wildly different ways, etc.
Communication is a two-way street, it’s partially on them to tailor their message to their intended audience, but it’s also on the audience to interpret that message, however they may receive it, in a way that makes sense to them, and it’s on both halves to clarify things and make sure the meaning is being effectively delivered and received.
If you’re getting links and videos from people to explain their positions, odds are that they feel that the information you’re looking for is in their, and probably presented in a better way than they would be able to themselves. That’s probably how it was presented to them, and in the way it was presented it made a lot of sense to them, and that’s the best way they know to present that information to you. From there it’s on you to watch or read what they sent you and try to interpret it. If you don’t want to do that, then you’re the one being lazy, and not in the good way. And from there if you need clarification, ask for it about specific parts that aren’t making sense to you. You can’t sum up a 10, 20, 30 minute or hour+ long video in a few sentences and not loose a whole lot of context and details, it’s on you to explain what’s not making sense.
And if your counterpoints aren’t getting through to them, it may be on you to find a different way to explain it, if they’re sending you videos, it may work better to send them videos back than to flood them with paragraphs of text that they may not absorb properly.