I can't prove this, but as someone who has noticed recent changes, I believe this has been also achieving attention of the leadership at HN and moderation behavior/flags/system has changed.

Certain opinions, topics, responses get flagged greater now; ones that disagree with a certain political standpoint or that criticize the intel community apparatus get flagged and censored now here. I used to see flagged content where the OP was removed only for bigotry and clearly abusive cases, now its for cases where people feel uncomfortable and strongly disagree.

edit: recently for the first time, I started to feel this is no longer a safe/trusted place for the original hacker ethos it founded itself on.