Actually the search and rescue potential is interesting. Maybe there could be an international symbol anyone stranded can make out of rocks or in the sand or whatever that the eyes in the sky automatically alert the authorities to.
PLBs/ELTs are much more scalable, at present. Someday, maybe AI will "watch" every m^3.
Just don't voice any "treasonous" opinions verbally, in the future, because Palantir Panopticon Next will bring SWATings, tax audits and extra pat-downs to whomever is labelled a foe. Gosh, there might even be a viable, non-tinfoil, future business model for rental of soundproof/TEMPEST meeting rooms in large cities (LOL, I hope not.) Total, real-time monitoring would be a massively-sharp, double-edged sword that has the potential to invade privacy like never before... and I fear people won't fight or even question it.
S.O.S. is the closest thing we have to that symbol. Perhaps we can let CAPTCHA-solving algorithms loose on all that image data...
The bigger issue is that the areas where people are most likely to be stranded are those least frequently surveyed by high-resolution imaging satellites.
Interesting idea, but it took me about 1.21 seconds to realize the potential for trolling this would have. Plus it would have to have enough entropy to not occur randomly.
I'm imagining a QR code made out of coconut shells.