It's literally the first rule of HN moderation that we don't suppress stories that are negative about YC or YC startups. More precisely, when stories like that appear, we moderate them less than we usually would. The reason is precisely what you said: long term trust is the most important thing. Also, before being moderators of HN, we're users ourselves, and wouldn't want the site to be moderated that way.
It's literally the first rule of HN moderation that we don't suppress stories that are negative about YC or YC startups. More precisely, when stories like that appear, we moderate them less than we usually would. The reason is precisely what you said: long term trust is the most important thing. Also, before being moderators of HN, we're users ourselves, and wouldn't want the site to be moderated that way.