Personally, while I appreciate when people add a “snippet of explanation”, I do prefer that to be in the comments. Not as the main text of the submission.

Making it part of the submission can feel like editorializing. If I want to read the artice, I read the article, if I want to read opinions / interpretations of the article, I read the comments.

Using the “text snippet” for opinions or interpretations can cause bias… and it also might encourage people to repost the same content multiple times just so they can post with a different bias.

I think the comment section is a more organized and suitable place for that. It also allows people to use their votes to decide whether the opinion/explanation deserves the upvote, separatelly from whether the link itself deserves promotion.