alt Hacker NewsI would expect someone commenting ELI5 on Hacker News to mean that they didn't understand the article directly, so pasting several paragraphs verbatim is not particularly helpful to them. If you think that the article is clear, and they're still asking for clarification, it's a sign that you've probably overestimated the clarity to someone with less experience in the subject (as always, relevant xkcd for this: https://xkcd.com/2501/)
That's fair, I had assumed they hadn't read the article at all ;) If they have, it would have been nice to know which parts of the problem definition the paper describes as "simple" they struggled with, otherwise I default to "I haven't read the article and would like a summary for a technically inclined layman"