I'm biased as I've not been a beginner dev for nearly 20 years, however I have found Copilot is pretty helpful for is learning Rust. In combination with Intellisense, it helps ease some of the mental overhead of the syntax, letting me focus on learning the important bits of the language. It helped me go from opening up a book on Rust to having a working tool in about a week.

I won't pretend that it's turned me into a senior engineer, of course, but it's definitely gotten me over the 0 to 1 problem much quicker than I think I could have without it nudging my code in the right direction.

For what it's worth, I don't ask Copilot to write the code, I just use it as an advanced auto-complete, reading the suggestion to see if I agree with it before hitting tab.