These are devices from simpler times: no networking stack, not even an OS, sometimes not even firmware, just the basic function encoded with transistors. There's literally nothing to run on. Think water heaters, not RPi.
> even NTP can't save ou if you shift the time too much, so it's a good thing it's only ~6 minutes so far.
Only for the initial step, or if the frequency of the quartz crystal is too fast/slow. The NTP daemon continuously adjusts the clock frequency, so if it was already running and synchronized, the shift will never be more than a few milliseconds.
