This is remarkable if you consider how much it must wound Apple's pride to make this deal with their main rival in the smartphone software space, especially after all the fuss they made about "Apple Intelligence". It's a tacit admission that Google is just better at this kind of thing.
I don't use it for large-scale code generation, but I do find it useful for small code snippets. For example asking how to initialize a widget in Kendo UI with specific behavior. With snippets, I can just run the code and verify that it works with minimal effort. It's often more about reminding me of something I already knew rather than discovering something novel. I wouldn't trust it with anything novel.
In general, I think of it as a better kind of search. The knowledge available on the internet is enormous, and LLMs are pretty good at finding and synthesizing it relative to a prompt. But that's a different task than generating its own ideas. I think of it like a highly efficient secretary. I wouldn't ask my secretary how to solve a problem, but I absolutely would ask if we have any records pertaining to the problem, and perhaps would also ask for a summary of those records.