Indeed: The act of actually typing the code into an editor was never the hard or valuable part of software engineering. The value comes from being able to design applications that work well, with reasonable performance and security properties.
Then why did most software fail to do that even before the advent of LLMs?
It wasn't the hard or valuable part of software engineering, but it was a very time-consuming part. That's what's interesting about this new era - the time-consuming-but-easy bit has suddenly stopped being time-consuming.