My favorite was when Google revealed Project Genie a month ago (which lets you generate video game worlds with AI, basically) and stocks for game companies immediately dropped. Anyone familiar with games and gaming knows that what Project Genie offers (essentially empty worlds with minimal interactivity that you can just kind of wander around in, and they struggle with simple things like object permanence if you look away) knows that this isn't real competition for actual games, but the markets reacted anyways.