We Already Externalized Muscle. Now Mind.
For most of history, physical work was muscle. Then steam, combustion, and electric motors took it. Human muscle became a rounding error in the global energy budget. Cognitive work is on the same curve, compressed in time.
When the price of a scarce input collapses, supply floods and demand expands. Cheaper engines did not reduce coal use. They multiplied it. Cheaper cognition will not reduce thinking. It will multiply it. Most problems on Earth currently go unthought about because thinking is expensive.

