A Quashed Plot Never Spoils

BE WARNED: If you're sensitive to spoilers, be ready to turn down the volume! Andrew and Adam are roommates and avid media consumers. Andrew badgered Adam to start watching one of his own favorite shows, and Adam eventually gave in. However, Adam says an off-hand comment from Andrew -- spoiler alert! -- ruined one of the character's story arcs for his friend. Should Andrew be held responsible for ruining his friend's viewing experience?