lasercat

Another exploration of this theme was in an episode of Doctor Who (Smile) which features a colony with nanobots that are optimized for happiness, with disastrous results: https://en.wikipedia.org/wiki/Smile_(Doctor_Who) - "The Vardy were programmed to help construct and operate the colony and make the colonists happy, monitoring the emotional state of the colonists through the emotion badges and avatars. When one of the flight crew died of natural causes, it created grief among the crew, something the avatars were not programmed to register. The Vardy took this as a sign of disease and killed those who displayed unhappiness. This created a "grief tsunami" which rapidly wiped out the flight crew, and will likely wipe out the waking colonists when they discover what happened."