It is an interesting question, and one I think about once in a while. My recall of specific facts from books I've read is pretty terrible (not sure if this true for others, or if it is related to my aphantasia in any way). That's true both for fiction and non-fiction I read. That said, I do feel that a certain amount of knowledge does remain, somewhere below the surface. I can carry on a conversation on a variety of topics, concepts that I have encountered before are processed faster, my worldview shifts and expands. I have general awareness of Mihaly Csikszentmihalyi and his work :) Is the benefit substantive? Hard to say. But I enjoy the process and get to be a slightly more well-rounded person, so why not.
