> Just today, I spent an hour documenting a function that performs a set of complex scientific simulations. Defined the function input structure, the outputs, and put a bunch of references in the body to function calls it would use.

So that's... math. A very well defined problem, defined very well. Any decent programmer should be able to produce working software from that, and it's great that ChatGPT was able to help you get it done much faster than you could have done it yourself. That's also the kind of project that's very well suited for unit testing, because again: math. Functions with well defined inputs, outputs, and no side-effects.

Only a tiny subset of software development projects are like that though.