Earlier quoted context omitted.
You could always go for Xtensa, PIC/AVR, or 68k. Still plenty of those around - although ARM has rapidly been eating their lunch the last few years.
PIC and AVR (along with 8051 and 6502 based designs) are still used in current consumer products reusing older designs. Yes, ARM Cortex-M0 can cost the same while offering 2x the processing processing power, but redesigning the PCB and rewriting the entire codebase for a new MCU would offset the processing power gains, which are not needed anyway. Most white-label consumer goods just need to poll some keypad buttons,…
You can get a 48 MHz RISC-V from WCH (a big 8051 supplier) or Cortex-M0 from Puya for $0.10 to $0.15 depending on whether it's an 8, 16, or 20 pin package. Both the CH32V003 has 2 KB SRAM and 16 KB flash, and the Puya 3 KB SRAM and 20 KB flash. You get the above prices for the WCH at qty 50 (i.e. $5 - $7) on their Aliexpress store, plus a couple of bucks shipping.
Being "too powerful" for the job is irrelevant if it's cheaper anyway. Plus easier to use because both use standard GCC/LLVM, support debugging etc.