"Literacy used to be a very subtle concept that meant linguistic sophistication. It used to denote a skill that could be developed to arbitrary levels of refinement through practice. Literacy meant using mastery over language — both form and content — to sustain a relentless and increasingly sophisticated pursuit of greater meaning. It was about an appreciative, rather than instrumental use of language. Language as a means of seeing rather than as a means of doing.
Reading and writing — the ability to translate language back and forth between oral and written forms — was a secondary matter. It was a vocational pursuit of limited depth.
The written form itself was merely a convenience for transmitting language across space and time, and a mechanism by which to extend the limits of working memory. It had little to do with language skills per se.
Confusing the two is like confusing the ability to read and write musical notation with musical ability. You can have exceptional musical ability without knowing how to read music. And conversely, you might have no musical ability whatsoever, but still be able to read and write musical notation and translate back and forth between the keyboard and paper. Being able to read and write musical notation really has almost nothing to do with musical ability..."