Unlike inebiration, dyslexia is in fact visual by definition; it has to do with having difficulty reading, even in the absence of other cognitive difficulties. It's just not something that occurs due to some issues in the visual pipeline, which could give it a "pixel level" representation/explanation. However, the entire pipeline from the cornea of your eye and retina, through the optic nerve and back to the visual cortex, is all visual.
It's plausible that we can manipulate the raw input signal in order to recreate a similar semantic handicap later in a normally functioning pipeline, such as slowed reading due to not being able to resolve the order of letters in a word.
The demo was inspired by a particular dyslexic's remark that the letters seem to "jump around" for her.
This could be a "piece of the puzzle"; of course we can't naively believe that this reveals everything that dyslexia is about, in all its manifestations.