At some point in young people, the ability to learn to read proficiently fades and is gone. There is a small window that, if you miss it, will never open again, so she will never learn to read properly, like a 6 year old child can.
The adult brain just cannot make those new connections necessary to correlate printed matter with thoughts and words...................
You feel there is no hope for adults to learn to read? The evidence does not support that. Adults can learn to read if they are motivated.
This woman has had 23 years to sign up for adult education. She did not.
I disagree. For example, lots of adults learn languages with other writing systems, such as Japanese or Arabic.