Something that I still don't understand:
Why do these dongles, this one and SX OS one, need battery/capacitors in the first place?
Don't they get powered by the switch itself? Doesn't the Switch connection send power to the adapter? Or is the Switch not able to power the dongle up?
Because in order to send the payload, you need a powered device DURING recovery mode. During RCM is the period of time where the Switch won't send power out of its USB C port, thereby whatever is sending the payload in must be powered. The SX Dongle does this by charging capacitors when the Switch can power on in normal use while MTX dongle relies on batteries.