I don't think it has much to do with ethics in the usual sense. It's all about tribal allegiance. Facebook and the like are the enemy. Anything that seems to bother the enemy is cheered. There is no thought that laws apply generally. It reminds me of that old internet meme about conservatism. There must be in-groups whom the law protects but does not bind, alongside out-groups whom the law binds but does not protect.

I think you could make a serious argument that the CEO killing was self-defense. But it's not going to really change anything. Maybe the successor is less ruthless but they will be making decisions in the same social context; facing the same incentives and disincentives.