From their own internal metrics, tech giants have long known what independent research now continuously validates: that the content that is most likely to go viral is that which induces strong feelings such as outrage and disgust, regardless of its underlying veracity. Moreover, they also know that such content is heavily engaged with and most profitable. Far from acting against false, harmful content, they placed profits above its staggering—and damaging—social impact to implicitly encourage it while downplaying the massive costs.