GitHub Copilot is just intellisense that can complete longer code blocks.
I’ve found that it can somewhat regularly predict a couple lines of code that generally resemble what I was going to type, but it very rarely gives me correct completions. By a fairly wide margin, I end up needing to correct a piece or two. To your point, it can absolutely be detrimental to juniors or new learners by introducing bugs that are sometimes nastily subtle. I also find it getting in the way only a bit less frequently than it helps.
I do recommend that experienced developers give it a shot because it has been a helpful tool. But to be clear - it’s really only a tool that helps me type faster. By no means does it help me produce better code, and I don’t ever see it full on replacing developers like the doomsayers like to preach. That being said, I think it’s $20 well spent for a company in that it easily saves more than $20 worth of time from my salary each month.