GitHub Copilot is the most useful in the hands of experts.
For getting the most out of AI, you need to be an expert in your domain.
You need to know how to ask the right questions, write the correct code.
You need to know how to be able to determine which answers are correct for your situation. Decide which suggested code is the best for your situation.
Then it is the most powerful.
We already experienced this 25 years ago when search engines became available. Search engines are more powerful if you know what you are searching for. And if you know which result from the extensive list is the answer you are looking for.
Being an expert is still important in the new world of AI. AI is a tool that will make great experts even greater.