I have most of the symptoms described by the OP, including a severe difficulty focusing on movies/books. For me, it's basically that my mind wonders if I'm not

I have most of the symptoms described by the OP, including a severe difficulty focusing on movies/books. For me, it's basically that my mind wonders if I'm not very interested. It's my mind's default mode of operation that I think about everything related to the thing I just thought about. Comes in very handy when programming, but is kind of annoying when trying to get through some mediocre material. Something worth noting is that my focusability seems directly based on how interested I am, not how action-packed something is. For example I have no problems watching the 1981 German classic Das Boot, where people just sit in a submarine for 3 hours. However something that is popularly belived to be made for ADHD people like The Transformers is excruciating for me even though there's so much going on visually every second. Stimulants like Adderall make me even more focused on things I could focus on already sober, but also make me even less focused on things I don't care about. So basically just intensifying my natural tendendices, as opposed to changing them.