It's definitely as good as junior dev at a lot of tasks but you always have to be in the driver seat. I don't ask junior devs to write functions one at a time. I give them a task, they ping me if they need something, but otherwise I hope I don't hear from them again for a while.

I don't see AI replacing that. AI is a tool with the instant Q&A intelligence of a junior dev but it's not actually doing the job of a junior dev. That's a subtle distinction.