The word they usually use is "tone-policing", followed by a snide order to "Google it". I think this is a misuse of an important concept. It is unreasonable and unfair to expect people to speak calmly about racism when they have been exposed to it their entire life. (Amazingly, many black people can do it, but that should be recognized as an act of heroism, not as a requirement of courtesy). I think one of the points of the article is that it is a lot easier to control anger about racism when it is based on empathy rather than on direct experience. Because that anger interferes with effective communication, those of us with privilege have an obligation to keep that anger under control, and not just indulge our self-righteousness when we encounter racism.