Also, when we humans are tricked into perceiving a remote mind, we automatically assume it has a memory like us, or at least like large animals.

In other words, there's a story-document between a SherlockHolmesBot and UserPlaceholder that's growing like a crystal formation. Some software sees "Sherlock Homes Says" and then "performs" the dialogue at us, and we then assume Sherlock Holmes exists with a mind and memory, rather than being a facet of a text-story.