Exactly true. I've had the experience of implementing a programming language in two different languages. The first time it took half a year. The second time it was done in a month, because it was really only a matter of translating all of the code from one c-style imperative language to another, and swapping out the important library code and function calls.

Maybe AI can take that process from a month down to 3 days, and that's great and all, a 10x improvement! But you don't go from 6 months to 3 days without doing the 6 months first.