This is from almost 20 years ago [0] and the original stretches back almost 30 years now [1].
[0] https://www.nngroup.com/articles/how-little-do-users-read/
[1] https://www.nngroup.com/articles/how-users-read-on-the-web/
I've seen where when AI is asked a question on how to use some particular feature of a piece of software it couldn't get a working answer. I read the documents myself and was just as confused. Then looked up customer tickets around said feature, and they were confused too.
I've taken that as a pretty good metric that if AI can't parse your documentation, your documentation is bad or wrong and needs to be rewritten.