I'm definitely against any tweets calling for the murder of anybody, I'll say that. But the "anti-harm" movement is not as benign as you think. For instance, see the firing of David Shor, who merely tweeted a study comparing the effectiveness of violent and nonviolent protests. There's an instance of someone who tweeted AGAINST harm, in that he was advocating for nonviolence. Yet he was still censored.
This article does a good job outlining some of the craziness: https://www.theatlantic.com/ideas/archive/2020/06/stop-firin...