alt Hacker NewsFlagging isn’t only in case of breaking the guidelines. From the FAQ:
What does [flagged] mean?
Users flagged the post as breaking the guidelines or otherwise not belonging on HN.
In other words, submissions get flagged that users believe don’t belong on HN. LLM-written submissions can be one such case.
"Not belonging on HN" is an open invitation to flag anything someone disagrees with. Many posts are flagged simply because they express an unpopular opinion.
Community moderation won't fix this problem. It can only be mitigated if the site owners invest significant resources in addressing it. And judging by how little YC actually invests in HN, I wouldn't hold my breath. This website will succumb to this problem just like most others.