I agree with that dyslexia is irrelevant to how smart you are. I also know lots of smart people with dyslexia. And it's not an excuse for being completely clueless about everything (not saying Dianne is using it as an excuse). You don't need a high education or books to still be well-informed. All it takes is a bit of curiocity, interest, observation and the willingness to listen to people, absorb what is being said and ask questions. This is where I think Joe and Dianne drift apart.
I'm not saying Joe is super intellectual, but he seem like a genuinely curious guy who process information easily and cares about a lot of stuff. He enjoys learning more, even if it's outside his interest area. I don't think he has s genuine interest in anatomy or medicine but I've still seen him answering physiological questions correctly. He can quote movies he's only seen once because things just stick with him, and he often uses stuff like that as references when communicating. I don't think he lies or tries to seem smart when he says he enjoys documentaries, conspiracy theories and game shows, I genuinly think he enjoys it, no matter the subject.
Dianne seem to have been living in a dance bubble and never really cared to develop any kind of knowledge about anything that doesn't interest her. This girl grew up during the early 2000's yet she has no idea who the fictional character Gollum is, which is just one rather mindblowing example. You don't need to have read the books or even seen the movies to know who Gollum is, it's just something you probably should have picked up on at some point. But she doesn't care, like someone said, she's happy being clueless. I'd lose my head too, and I'll keep on arguing that Joe will as well some day.
I agree with what others have said that her cluelessness probably does give Joe some kind of confidence boost and makes him feel superior, but I also believe you can only take so much. I don't think it's that far reached to anticipate that this could become a problem and eventually break them up. I have several friends that I don't see anymore because they are completely uninterested in talking about anything that isn't part of their interests, it's annoying and frustrating and you start to feel like a teacher having to explain everything and update them on recent events. It might not be a big issue when you're in your late teens (hence why their fandom would never point this out) but as you grow older you notice how much communication and intellectual exchange play part in your relationship, especially today when there's s lot of things going on in the world that people feel the need to talk about. The fact that Joe can't speak publicly about politics or "deep subjects" probably does, if anything, give him the need to speak about it privately, but I struggle to see him doing that with Dianne because she doesn't seem to have any interest in learning things that aren't directly affecting her.
