>>67308I believe Maya has a perfectly adequate intelligence, considering her chronic ADHD, and a seeming lack of quality education.
It is, however, completely fair to criticize her social skills, and her scathingly pessimistic worldview.
I don't think these traits are completely unfounded however, it's quite possible that her sedentary lifestyle and lack of attention from anyone besides her adopted sisters has aggravated or even been the root cause of these issues, and without any outlet to vent her frustrations, they have only festered more and more as she has grown up.
TL;DR It's not entirely fair to harshly judge Maya's intelligence, due to her unfavorable circumstances and mental issues.