Feast your eyes on this: https://cpldcpu.com/2019/08/12/the-terrible-3-cent-mcu/

The HT68F001 stands out: 512 words of program flash and 16 bytes of RAM. ... can only be clocked from an internal 32 kHz oscillator. Since each instruction takes 4 cycles to execute, this results in only 8000 instructions per second!