I'm not sure why people try and go for the cheapest microcontroller. These things all have unit prices in the single digit dollars or less in actual production costs. Finding a cheap microcontroller is entirely about finding a cheap reseller of whatever you're trying to get rather than finding a cheap part specifically. Only when you get to truly large volumes such that you can get volume discounts does unit price re…
However, low end 32bit devices are also available from reputed suppliers. In fact, STM just announced the STM32C* series which is also aimed at replacing 8 bit controllers.
The cost benefit may only be true for low numbers and when sourcing from distributors. I am fairly certain that the price advantage is much less when talking about actual production volumes
*https://www.st.com/en/microcontrollers-microprocessors/stm32...