Mark Zuckerberg spent more than five hours on the stand in Los Angeles Superior Court on Wednesday, testifying before a jury for the first time about claims that Meta deliberately designed Instagram to addict children. The headline from most coverage was the spectacle: an annotated paper trail of internal emails, a 35-foot collage of the plaintiff’s Instagram posts unspooled across the courtroom, a CEO growing visibly agitated under cross-examination. The more important story is what Wednesday’s...