These intelligences would still require power to run. Right now, even 1 trillion computers running at 100 watts would cost somewhere upwards of 50 billion dollars an hour, which is a far cry from “working without pay”. Producing these 6 trillion general intelligences you speak of would also be nontrivial.
That said, even one “human equivalent” AI could (and almost certainly would) far exceed human capabilities in certain domains. Several of these domains (i.e. self-improvement, energy production, computing power, and finance) would either directly or indirectly allow the AI to improve itself. Others would be impressive, but not particularly dangerous (natural language processing, for example).
I just finished the survey. I had given myself a 15% probability of being correct on the Newton question, and was off by significantly over 15 years. However, I should have calibrated that as 30%, as I knew the century but had no idea when in the century he published the book.