I do agree. Neither the HN Guidelines [1] nor the FAQ [2] are clear about what expectations they have for downvotes (unless I'm missing something). I never saw the original comment when it was, I assume, greyed out, prompting the second poster to ask about the downvotes. It is second-highest ranked now, so I assume the downvotes are a minor component to its rank.

[1] https://news.ycombinator.com/newsguidelines.html

[2] https://news.ycombinator.com/newsfaq.html