I think you're missing the point that most of the things that make this hard for people are also what makes it hard enough for them to read that they won't do i

I think you're missing the point that most of the things that make this hard for people are also what makes it hard enough for them to read that they won't do it well, even for things like emails. Reading is a skill, and it's not the same as being (technically) literate. For someone who's a competent reader, there's nothing at all more intimidating about being asked to read a page from a book (you can choose the book, but a page from a book is not a "wall of text," and the book's publication also implies at least some pre-screening for accessibility) than being asked to have an impromptu conversation about where to find the potatoes, and whether you know any tasty recipes for them. Most people don't read well. They read well enough to understand street signs before they pass them, or to get through an article intentionally written to a 6th grade level. But anything where the details are important? Or that requires explanation? They either cannot do it, or find it so difficult that they won't.