It doesn't matter that very few devices connect. That's the only reason they have to volume to be affordable at all.

If you took the total cost of having satellite coverage available and divided by the amount of satellite assisted rescues needed per year, the amount that a satellite company would need to charge just to break even would absolutely be thousands. Satellites are expensive. Rescues are rare.

The only reason it's able to be something regular people can pay is because there are hundreds or thousands of people who don't ever use it paying into the pot. Without those people, the economics don't work. "Unlimited SOS" isn't any impact to the network at all, because frivolous use gets punished by other people.

Apple being able to get you literally any discount at all is already a value add. (And they've completely footed the bill so far).