What you say is true, of course, but at the same time it's true of any Turing-complete languages, and therefore, meaningless. I'm not a bad engineer because I don't have time to start every project from the bare metal. Runtime and libraries make a huge difference in the real world. Sure I'd love to spend the time really diving deep and making LISP into the perfect DSL for me, but the truth is, I can just use Python and go.