I interpret it differently. Layering and libraries were solved ages ago (although we have many, many more layers now). This isn't what people were striving for

I interpret it differently. Layering and libraries were solved ages ago (although we have many, many more layers now). This isn't what people were striving for when they talked about reuse in-the-large. It was more about domain models and objects like having a common Customer entity or reusing an insurance domain object model across different customers. Horizontal re-use has always been possible but vertical reuse is a pipe dream.