Future US made IOT devices will mostly be ARM Cortex M33 and M0+ microcontrollers. They have the latest cryptography and safety features built-in and nice libraries. It's surprisingly difficult to find out what fabs build them. Maybe someone here can chime in?
Those things mostly don't have built in wifi which is annoying, because then you need a separate chip for the wifi. Atmel is the exception, arduino even makes a dev board with it, but it is $35 vs $8 for a esp32 devboard.
