Elon Musk made plain his view of the widespread advertiser withdrawal this month from X, formerly . “Don’t advertise,” he urged any marketer with misgivings. “Somebody’s going to try to blackmail me with advertising?! Blackmail me with money? Go f–k yourself. Go. F–k. Yourself. Is that clear? I hope it is.” The billionaire tech exec’s remarks came at the beginning of an occasionally awkward, epic-length but frequently compelling session capping the New York Times DealBook Summit. (Watch the segment about advertising in the clip above.) Moderator Andrew Ross Sorkin noted that Disney has been among the companies pausing ads on...