On Monday’s segment of his prime-time show, the Fox News host Tucker Carlson cast doubt on the reasons behind the worldwide unrest prompted by the police killing of George Floyd in Minneapolis last month. “This may be a lot of things, this moment we are living through,” Mr. Carlson said. “But it is definitely not about black lives, and remember that when they come for you. And at this rate, they will.” Since he made those statements and others, prominent companies including the Walt Disney Company, Papa John’s, Poshmark and T-Mobile have distanced themselves from “Tucker Carlson Tonight,” joining other...