Is Confidentiality Null & Void After Both The Therapist & Their Client Dies?

Nobody knew the answer in the Mental Health section, and my cl is online, so it takes forever for me to finally reach my Professor. So, I wondered if those that frequent this section would know. I'm asking because I notice in many of my Psychology text books, they have cases that Freud, Carl Rogers, or other Psychology theorists, conducted. They have the information of the client, and in some instances, the script of their therapy session. Also, in one of my cles, we got to watch a video taped session of one of them....I believe it was Carl Rogers. I just wondered how such information and access, that is supposed to be private, has ended up being shown in clrooms and on tapes? Does confidentiality no longer matter after both have died? If that's the case, can anyone's case and therapy sessions, be published in text books, and shown to students...after the two have died?