ESP8266/32 is slightly over a $1 but still within the spirit of “more like $1 micro”.
Confining more strictly to $1.00, STM32F030F4P6 (48MHz 32-bit M0) is in spitting distance to a 386 or 20MHz 68030 for some workloads. (50 MHz 486-DX2 was introduced in ‘92, but the typical desktop PC of 1992 was much lower spec.)
