Rich Hickey presents on Complexity and hammers on easy (low-cost right-now) versus simple (separation of concerns).
"Let's all write parsers."
Hickey also kicks unix because although pipes = composability, output and input = free-form text. We combined data exchange with user interface, and user interface usually won that fight.
Say data exchange won; would it help us to rewrite our programs to output JSON and our shells to pretty-print* JSON?
[*] The cynic points out that people would then spend time customizing their pretty-printers.