As much as I'm finding LLMs incredibly useful, this "world where computer languages disappear" doesn't resonate with me at all. I have yet to see any workflows where the computer language is no longer a critical piece of the puzzle, or even significantly diminished in importance.
I think there is an important difference between LLM-interpreted English, and compiler-emitted Assembly, which is determinism.
The reason we're still going from human prompt to code to execution, rather than just prompt to execution, is that the code is the point at which determinism can be introduced. And I suspect it will always be useful to have this determinism capability. We certainly spend a lot of time debugging and fixing bugs, but we'd spend even more time on those activities if we couldn't encode the solutions to those bugs in a deterministic language.
Now, I won't be at all surprised if this determinism layer is reimplemented in totally different languages, that maybe are not even recognizable as "computer language". But I think we will always need some way to say "do exactly this thing" and the current computer languages remain much better for this than the current techniques to prompt AI models.