> but it does a really good job teaching kids to read; and for the few kids who fail to learn to read,
Depending how you define illiteracy many children can't read. About 20% of children are functionally illiterate when they leave US highschool.
https://en.wikipedia.org/wiki/Literacy_in_the_United_States
> The study, the most comprehensive study of literacy ever commissioned by the U.S. government, was released in April 2002 and reapplied in 2003 giving trend data. It involved lengthy interviews of over 90,700 adults statistically balanced[clarification needed] for age, gender, ethnicity, education level, and location (urban, suburban, or rural) in 12 states across the U.S. and was designed to represent the U.S. population as a whole. This government study showed that 21% to 23% of adult Americans were not "able to locate information in text", could not "make low-level inferences using printed materials", and were unable to "integrate easily identifiable pieces of information."