The application writing its state to the executable is basically Smalltalk (or Lisp). It's an extremely powerful way of writing software, IMO.

Or Forth. But all of these are extreme spaghetti-bait too. Being able to see all the code that goes into an executable, and generate a clean one using only that code, is important for good development hygiene, which of course they didn't know yet in the 1970s. Imagine trying to use version control on a REPL - it doesn't work - you have to version control the commands that go into the REPL and running them on a fresh REPL every time.