I know a well engineered and properly maintained and tuned engine takes a lot less energy to start... but that is only one variable of the Auto Stop/Start functionality.
What I am thinking about is how long you may be sitting there with the engine stopped and no charging, A/C or heater running, lights on, maybe seat heating, stereo playing all draining your battery... There have been a number of posts now that Auto Stop/Start stops working on the car because the computer determines that the battery will not have the required energy to properly support this function, and even when it does, I have had occasions where the car's engine restarts before I plan to pull away because the current load is already depleting it to a questionable point.
From what I recall from an article written when these systems were debuting, the biggest victim in your engine is the crankshaft. As I understand it, the crankshaft is strained most during start, as it's normally driven by
the pistons in a rhythm, whereas during start it's driving them
out of rhythm.
Auto Start/Stop (AS/S) engines have redesigned internal parts in consideration of this (how well remains to be seen).
I would not worry too much about the system in your Porsche. If it bothers you, just use the defeat button. AGMs are deep cycle batteries, have been around for decades, and should pose you no problems. Besides, AS/S is a city thing. Driving across Montana it won't do squat for anything, except needlessly boost the purchase price of the car.
FWIW, you are far more likely to be affected by an such a system by getting stuck at an intersection when a 3rd-owner AS/S Hyundai dies because of a driver who doesn't do any maintenance.