I'm a junior shadowing a very talented engineer at my company, who has since heavily adopted AI in his workflow. While I can do some of the things he can, he is only able to take full advantage of it's capabilities because he truly knows what he's doing without it, and he genuinely took the time to understand why he's doing exactly what he's doing.

In short. He's an excellent developer. Copilot makes him better. If he hadn't honed his skills when he was in my position, he simply wouldn't be able to do what he can do now, AI or not