It says "9 hours ago" to me. Is this one of those situations where HN reposted the post and the comments as well? I wish the date and time were kept accurate instead of being confusingly changed.

Yes it is. https://web.archive.org/web/20241226052659/https://news.ycom... (Archived page is from 2024-12-26, and you can mouse over the "# minutes ago" links in the title and comment to confirm.)

Huh, for me in Hacki on Android both the original comment and the root post say "4 days ago"