Using "cancel" to mean rejecting someone appeared in Black music and film, including the 1991 movie New Jack City and a 2010 Lil Wayne lyric. Black Twitter users spread it in the mid-2010s as a way to stop giving attention or money to people who caused harm. Boycotts have a much longer history in Black organizing, including the Montgomery Bus Boycott of 1955 and 1956.
By 2020, the phrase had become a political label. A Pew Research Center survey in September 2020 found that 44% of US adults had heard at least a fair amount about cancel culture. Many conservatives use it to describe what they see as a climate of censorship, while many progressives say the term is used to avoid criticism.
ARD's reading is that the debate is about who gets held accountable and by whom. For most of US history, ordinary people, especially Black people, had little power to answer public figures who harmed them. Social media gave them a tool. Whether a particular response is fair depends on the facts, the harm and whether there is a path to repair.