I have personally become convinced that REPL-driven development is a terrible name for what we do, precisely because of the reasons outlined above. People associate “REPL” with a specific place where you put code, but it’s not about the REPL as a place, that is entirely secondary, it’s about the interactivity that is possible when communicating with a live process.
We don’t need to invent new terms for this, we just need to go back to the roots. This has been known since the 70’s as interactive development. Here’s a paper from 1978 that digs into what that means. (hat tip to @jackrusher for that).