So, what is the state of concurrency programming in MicroPython? I see an RFC from 2014  and a thread from the same year , but I don't know if this is in MicroPython (like is generators there?)?
The RTOS of Arduino, is to the best of my knowledge, not much useful .
Now, anybody who knows about Zephyr and the M5?
 RFC: Cooperative concurrency model of choice for MicroPython
 uasyncio - asyncio-like cooperative multitasking framework for uPy
 Arduino concurrency (Blog note, same disclaimer as above)