Because it exposed the interpersonal dealings of people who work at Sony. Whether it's that Trebek sometimes gets mad when asked to deal with unreasonable peopl

Because it exposed the interpersonal dealings of people who work at Sony. Whether it's that Trebek sometimes gets mad when asked to deal with unreasonable people, or that execs sometimes say really terrible things about people when they think the email is only between the two of them, or the future of companies that Sony execs are board members of (such as Snapchat) where there is lots of confidential information being discussed about the future of Snapchat and where it believes the current status of messaging lies.