It is not a reset. It is jump starting the 12v battery with the larger battery if the 12v is drained. Then you can start the car and the 12v battery gets recharged.unless resetting the battery also recharges the battery, I don't see why this is relevant to any discussion about the Taycan.
The start button would have to have a separate power system (not difficult) isolated from the 12V system - it could then instruct the traction battery to charge the 12V system, if required.They could tie it in to the Start button logic I guess? That must have to start up a bunch of different systems already.