There's a tragedy of the commons here, where the majority is going to the comments first without reading the article, expecting the other commenters to inform them about the article. Given this common practice, what makes you think you can get right to the actual information by looking at the comments? They're often less reliable than the articles themselves.
My comment included
There is a Nash equilibrium where experts and those who are interested read/know the topic of the article and write some commentary about it. The most insightful comments usually receive more upvotes from everyone (including non-readers). reading the top comments is thus generally a good timesave to risk of being misinformed tradeoff that many users have decided to be worth taking.
Being less reliable can be acceptable if it reduces the time to read by 10x or more.
That's highly questionable.
They're link aggregators, so threads start from links. But nobody reads the linked articles, they only head the "headline." In other words, the headline is the title of the thread, and the comments are a discussion starting from that title.
So what is the linked content? From the user's perspective, the linked article is just another comment. Which for users somehow make sense. The "author" is just an user with a site making a comment on a topic on their own website, while the thread are users without their own websites making comments on the same topic. If a single "comment" is just somebody's opinion, then it's highly likely most "are not worth reading," including the linked article.
So why is the link necessary in first place then? It certainly doesn't feel like it's needed. You could make a social media where to start a new thread you just type the topic and that's enough. We could also have the extreme opposite: we could have a social media where you also just type the topic to start a thread, but all "comments" must be links to articles.
I wonder if there's a social media like that. It would be interesting to compare what the threads look like.