It's a logical continuance of the current state of affairs. Even in the early 90s when these books were written, few people wrote entire applications in assembly language, or punched machine code into cards; they wrote in a higher-level languages that are eventually compiled into machine code, or were interpreted by other tools of which they know nothing about the internal workings.

Hell, we are inventing entire languages today that compile to Javascript, which in turn is interpreted or JIT-compiled by other tools. Or we write advanced HTML5 frontends that talk to advanced Node.js backends that in turn talk to legacy systems written in COBOL running on IBM mainframes. Programmer-archaeologists already exist.

Because GitHub.