> I will be surprised to reach AGI without nearing the Order-of-Magnitude of brain processing.
I have some theories that this isn't necessary. 1.) Just because the brain is a general-purpose machine great at doing lots of things, doesn't mean it's great at each of those things. Like when two people are playing catch, and one of them sees the first fragments of a parabola and estimates where the ball is going to land- a computer can calculate that way more efficiently than a mind, despite the fact that both are quick enough to get the job done. 2.) While the brain is great at, say, putting names to faces... a good CV machine can do the job almost as well, and can annotate a video stream in real-time.
Combining 1.) the fact that some problems are much simpler to solve with classical algorithms instead of neural networking, and 2.) that many brain tasks can be farmed out to a coprocessor/service, my hypothesis is that the number of neurons/resources required to do the "secret sauce" part of agi could be greatly reduced.