Dyslexia is one of many types of learning difficulties. There are many types of these difficulties and just about everyone has one to some extent or another. With dyslexia, the learning difficulty may range from a person with horrendous dyslexia who is functionally illiterate, to someone who is just fairly bad at reading and writing. In some instances, you'll find dyslexics who are actually okay at reading and writing seeing as the condition describes a wide range of cognitive problems, including things such as difficulty understanding directions, reading maps, and/or doing logical puzzles. You'd think that in fiction this would be portrayed accurately. You would be wrong.