I’m not sure how I feel about this. On one hand I’d like to avoid more skill bloat, but on the other hand I really like playing illiterate characters and having the trait explored more and getting NPCs involved could be a step in the right direction of making them more useful.
However, it would also be another case of a trait essentially becoming “free points” since to overcome illiterate permanently you just have to train it like any other skill. At least right now you need to have an NPC read to you, and in order for them to do so they also have to understand the context of the book, meaning you need to train them up the slow way if you know more about the topic than them.