A question that pops up from time to time is can I use an ESP32… to which the answer is usually
something like: “the ESP32’s ADC is known to have linearity problems.”
This article says, as of Nov of 2021 the issues with the ADC have been resolved by the manufacturer:
I couldn’t find anything on Espressif’s website, but I didn’t speand a great deal of time searching.
If true, it could mean recently manufactured ESP32s are now a viable choice.