Well, you can say that the title is a little bit misunderstanding. I do not want to compare these architectures, it's worthless.
I am trying to understand why an engineer could ever pick for his LoRaWAN node an ARM MCU. In my opinion, if someone trying to design a LoRaWAN gateway then an ARM MCU is a good/safe option. But if you want to design an ultrasonic sensor, an air quality sensor or a magnetic sensor, i can not find any benefits on using ARM MCU.
In my designs, i have done tests using 8-bit PIC (pic18lf46k22) and AVR (atmega328p) and i can say that on the above applications these MCUs are overspec!
So, the only thing left was the cost of the MCUs for making the "right" choice. Let's say at 100 pieces you can get an atmega328p at $0.98 per piece and for STM32F411RCT6 you need about $3.98.
My company is buying competitors products so we can check what they are using etc.
I have NEVER seen any other MCU architecture than ARM.
So this is really bad for me because i am thinking that i am missing something.
I really need advices/opinions from more experienced engineers than me.
*Reminder: * I consider as simple applications for me is to get data for one or two sensors and send them to the gateway.
P.S. We have a waste management project (40 sensors) running for 7 months and nothing "weird" happened. We are using atmega328p.