You might not know who Sneako is. But most any middle school or high schooler does. The 27-year-old streamer has made a name for himself as a political commentator, live-streaming as many as eight hours a day on Kick to spread extreme views that are teen boy catnip. The secret to his success? A willingness to say — to 1 million-plus subscribers on YouTube and 100,000 on Kick — what others aren’t, no matter how vile. He presents this as if the rest of the world is prevented from speaking the truth by corporate overlords, rather than the ideas being...