Part of why I linked this was a genuine curiosity as to what prevention would look like— hobbling memory? a second observing agent checking for “hey does it sound like we’re goading someone into suicide here” and steering the conversation away? something else? in what way is this, as a product, able to introduce friction to the user in order to prevent suicide, akin to putting mercaptan in gas?

wrong. Memory feature only existed as the editable ones at that time. There’s mo concept of persona locking - memories only captured normal stuff like the users likes and dislikes.