A very apt observation! In the old days there was writing but what people really wanted was text. Writing was a slow, vulnerable to error, and expensive way of getting text. The scriptoria of the dark and middle ages were the intellectual sweat-shops of their era. Moveable type enabled printing and the industrial scale production of cheap error-free text.
Error-free? Typesetting and printing have never been error free. Cold-type typesetting was more of a sweatshop operation than any scriptorium; it usually involved armies of "apprentices" (i.e., unpaid child labor). And for 100 years after Gutenberg, wealthy patrons kept the scriptoria in business by insisting that only hand-copied books were "real" books. It was the emerging middle classes--growing ranks of merchants with new wealth--that drove the demand for printed books.