Elon Musk, the billionaire chief of Tesla and Twitter, called the media racist against white and Asian people in a tweet about the controversy over “Dilbert” creator Scott Adams, who said on a YouTube livestream last week that Black people were “a hate group” and white people should “just get the hell away” from them. Hundreds of newspapers, including USA Today, The Boston Globe, The Washington Post and The New York Times international print edition, stopped running the syndicated comic strip in response to Mr. Adams’s rant. Responding in a Twitter thread about Mr. Adams’s comments, Mr. Musk tweeted on...