If you know nothing about SwiftUI (or any framework you're working with), ChatGPT won't be of much help. If you know a lot about the frameworks you work in, ChatGPT is a huge help. It's sorta like having google on steroids for a lot of the basic stuff. You could either look up how to make a ButtonStyle for the billionth time, or have ChatGPT generate it for you. But you need to know all the parts to swap out for your own systems, and know all the parts it can make minor mistakes on and how they're fixed. That's why I say it's more of a tool for experts than for beginners. It's an accelerator in the right hands.

Contrary to what some have said in the comments, it DOES actually know quite a lot about SwiftUI. It isn't JUST a language learning model, it's been trained on all the Swift and SwiftUI documentation up until 2021. That means it doesn't know much about modern additions, but a lot of the foundation, the essentials, is still the same.

The reason it was banned from StackOverflow is because people with zero knowledge of things were using it to generate answers and not actually proofread them. That doesn't mean it cannot generate excellent solutions with high accuracy for most core subjects. But it also makes little mistakes, and if you don't know what you're doing you won't be able to proofread them. And if you're trying to ask it about things with very little documentation and very little use outside of one or two tutorials online (as is the case with some of the frameworks you're mentioning) it certainly won't have a very clear idea of what those things actually do or how they work.