I agree with the basic idea, but there’s not some fundamental distinction between what we have now and true AI. Maybe we’ll find breakthroughs that help, but the systems we’re using now would work given enough computing power and training. There’s nothing the human brain can do that they can’t, so with enough resources they can imitate the human brain.
Making one smarter than a human wouldn’t be completely trivial, but I doubt it would be all that difficult given that the AI is powerful enough to imitate something smarter than a human.