> not sure why that would say they don't apply just to submarines though?

Because it isn't "possible" for modern submarines to assist with rescue. They're pathetically unstable on the surface. Vulnerable as hell to even drones. Don't have a deck to speak of where rescues could be held. And have a nuclear reactor inside–you can't take randos through the airlock.

The only "circumstances permit" place where a submarine might be able to help is if it's operating in friendly waters, with air support and naval support close by to ensure no e.g. drones make a run for it while it's on the surface. And even then, it would be a risky operation.