dang has commented about this before, and IIRC the gist is that he has access to a ton of data about user activity on the site, and that in the vast majority of cases where it feels like a story/comment/opinion is being brigaded or otherwise maliciously targeted en masse, the data hasn't backed that up. The community is a large and varied, so inevitably whatever opinion you or I holds, there are a ton of people who also exist here who disagree.
Do you track people who frequently flag stories and/or comments?
Do you collate those results against particular subjects? i.e. Any musk related story always gets flagged by $group
Do those groups/people always flag within X minutes of each other?
Do those groups/people match the general ___location of a random sampling of HN users, or do they differ in a statistically significant way?