We already know that Zuckerberg and his fellow oligarchs define "violence" as insufficiently enthusiastic adherence to the Death Cult. Here he is bragging about interfering with the Irish abortion vote by blocking pro-life ads.
Facebook's policy rationale has nothing to do with stemming violence. The real purpose behind these guidelines is to make those deemed heretical by the Death Cult de facto outlaws who are fair game for any type of abuse, up to and including death.
They haven't given a fig for what the average American thinks in a long time. Besides, this issue isn't restricted to America. See FB's meddling in the Irish elections on behalf of Moloch.