The higher numbers there (eg. 10²⁸) are irrelevant. It claims a single neuron is operating at 10¹⁶ operations per second—that is, as much computation is happeni

The higher numbers there (eg. 10²⁸) are irrelevant. It claims a single neuron is operating at 10¹⁶ operations per second—that is, as much computation is happening within a single neuron as is the sum of all computation between neurons in the whole brain! Bostrom's estimate of 10¹⁷ is much, much more reasonable. Note that this is still a number biased in favour of the brain, since for the brain you are measuring each internal operation in an almost fixed-function circuit, and for Summit you are measuring freeform semantic operations that result from billions of internal transitions. A similar fixed-function measure of a single large modern CPU gives about 10¹⁷ ops/s as well; the major difference is that a single large modern CPU is running a much smaller amount of hardware many times faster, and uses binary rather than analogue operations.