Experts in the AI and Big Data sphere consider October 2021 to be a dark month. Their pessimism isn’t fueled by rapidly shortening days or chilly weather in much of the country—but rather by the grim news from Facebook on the effectiveness of AI in content moderation.

This is unexpected. The social media behemoth has long touted tech tools such as machine learning and Big Data as answers to its moderation woes. As CEO Mark Zuckerberg explained for CBS News, “The long-term promise of AI is that in addition to identifying risks more quickly and accurately than would have already happened, it may also identify risks that nobody would have flagged at all—including terrorists planning attacks using private channels, people bullying someone too afraid to report it themselves, and other issues both local and global.”