I don’t know about ChatGPT, but Github Copilot can act like an autocomplete. Or you can think of it as a fancier Intellisense. You still have to watch its output as it can make mistakes or hallucinate library function calls and things like that, but it can also be quite good at anticipating what I was going to write and saves me some keystrokes. I’ve also found I can prompt it in a way by writing a comment and it’ll follow up with attempt to fill in code based upon that comment. I’ve certainly found it to be a net time saver.