All software written will not disappear. There is nothing keeping us from using partly undeterministic software (see: humans) to write deterministic programs.

What does the N in NP stand for?

I'm a bit joking, but we've been working in deterministic computation for so long, we don't even think of there being another way.

But seriously, I do view AI as the input to a deterministic machine. Junior engineers (well all engineers) aren't deterministic, and we've made processes to direct their behavior towards making better software. AI agents do a better job of following my processes than engineers. We move up the stack towards testing and verification rather than writing. That doesn't make me sad, after 40 years of coding, I'm kind of tired of it. I have more ideas than I can code, so I'm happy to give AI my ideas and have it code for me.

I had a former manager tell me that all technology problems are really people problems, now maybe all technology problems are all agent problems and we just have to get comfortable with managing agents like we got comfortable with managing people.