The main challenge I have found is getting ChatGPT 4 to produce correct vectorized code. Even given quite short procedural code snippets, it fails in repeated attempts to vectorize them correctly.
This isn't a failing specific to the Wolfram language, however: the same thing occurs with Python and Matlab.
What I am hoping is that Wolfram will eventually provide api connectivity between ChatGPT 4 and the Wolfram documentation library, which is organized very systematically and is replete with examples of function usage. Given this, and an ability to test its own code, ChatGPT should be able to improve its performance with WL programming, over time.