You're right that it does hallucinate a lot when it comes to MacOS API. I find that the hit rate is good enough to ask ChatGPT first, however, before diving deep into Apple documentation.
It's saved me quite a bit of time in terms of understanding how to use APIs as a client. I find the API docs that Apple provides are so bare bones and don't illustrate how the APIs are meant to be used, and you really have to search around for example projects or That One WWDC Video Where All Is Revealed. Asking ChatGPT first saves a bunch of time having to do all that searching.
It's saved me quite a bit of time in terms of understanding how to use APIs as a client. I find the API docs that Apple provides are so bare bones and don't illustrate how the APIs are meant to be used, and you really have to search around for example projects or That One WWDC Video Where All Is Revealed. Asking ChatGPT first saves a bunch of time having to do all that searching.