Re: Wrong way around!!!
Well, I'm sure OpenAI et al would tell you that a machine brain is many times more useful than a human brain of the same intelligence - because the machine brain, once trained, can be used to make millions of decisions simultaneously. So it only needs that 936 MWh once, to replace a million human brains that needed 3.5 TWh between them to train, and those weren't even consistent.
They would also tell you that it is not necessary for the AGI to be a superbrain or to understand the physical constraints of our world. It just needs to be omnipresent and people will worship it like a God. And it would be a God that they control.
Where I disagree with your post though is where you say "What is needed is ... ". I don't believe that AGI is "needed" at all. If it does ever come along, it will be one hell of a threat.
When I first played Deus Ex 23 years ago, I picked the ending where JC Denton merges with the Helios AI and becomes God.. Now in my late 30s, I would pick the ending where JC Denton blows up the whole complex and shuts down the Internet for everyone on earth. Let's go back to living in villages.
Maybe when I am older still, I will be grumpy and cynical enough to prefer the ending where we just kill Elon Zuckerborg Bob Page, and let the old secret government keep the AI for itself and do what it has always done.