Just a hundred years ago, we had one floating point operation per second in mechanical calculators. We got roughly 100 TFlops (fp16; probably much more accurate than human brain neurons) in a high-end gaming GPU now. That's 14 orders of magnitudes in a hundred years. I guess, 4 more orders of magnitude in another hundred years should be possible. We don't even have fusion power yet. A lot changes when power becomes a practically unlimited resource.