Essentially, the brain is massively underclocked because of design-space restrictions imposed by biology and evolution
The main restriction is power efficiency: the brain provides a great deal of intelligence for a budget of only ~20 watts. Spreading out that power budget over a very wide memory operating at very slow speed just turns out to be the most power efficient design (vs a very small memory running at very high speed), because memory > time.
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The main restriction is power efficiency: the brain provides a great deal of intelligence for a budget of only ~20 watts. Spreading out that power budget over a very wide memory operating at very slow speed just turns out to be the most power efficient design (vs a very small memory running at very high speed), because memory > time.