> just to have the exact same output, exact same time, but now "nicer".

The majority of code work is maintaining someone else's code. That's the reason it is "nicer".

There is also the matter of performance and reducing redundancy.

Two recent pulls I saw where it was AI generated did neither. Both attempted to recreate from scratch rather than using industry tested modules. One was using csv instead of polars for the intensive work.

So while they worked, they became an unmaintainable mess.