Intelligence is one thing, being able to figure out how get a task done (say). But understanding that no, I don't want you to exploit a backdoor or blackmail my teammate or launch a warhead even though that might expedite the task. Or why some task is more important than another. Or that solving the P=NP problem is more fulfilling than computing the trillionth digit of pi. That's perhaps a different thing entirely, completely disjoint with intelligence.
And by that definition, maybe we are in the neighborhood of AGI already. The things can already accomplish many challenging tasks more reliably than most humans. But the lack of wisdom, emotion, human alignment, or whatever we want to call it, lead it to accomplish the wrong tasks, or accomplish them in the wrong way, or overlook obvious implicit requirements, may cause people to view it as unintelligent, even if intelligence is not the issue.
And that may be an unsolvable problem because AI simply isn't a living being, much less human. It doesn't have goals or ambitions or want a better future for its children. But it doesn't mean we can never achieve AGI.
Oh, and to your first question, yes it's a huge number of jobs, maybe half of jobs in developed nations. And why not? If you can get AI to do the work of the scientist for a tenth of the price, just give it a general role description and budget and let it rip, with the expectation that it'll identify the most promising experiments, process the results, decide what could use further investigation, look for market trends, grow the operation accordingly, that's all you need from a human scientist too. Plausibly the same for executives and other roles. Of course maybe sometimes the role needs a human face for press conferences or whatever, and I don't know how AI would be able to take that, but especially for jobs that are entirely internal-facing, it seems like there's no particular need for a human. Except that maybe, given the above, yes, you still need a human at the helm.