I'm not sure an apology for murdering my family would be heard without a lot of anger and resentment. Other concepts such as revenge, retribution and other sentiments would likely also come to into play regardless of sincerity.

You make a good point about the snarky critique though. Having looked through a few of the dead comments on this post, a lot of people are very rigid about sensitivity training. There are a lot of parallels with SJW causes in how this is being approached.

(I am not equating those parallels with the validity of sensitivity training, only the rabid nature of the defence against criticism thereof I have seen).