GPS has always been available to get location information even offline. What you usually don't get at the user end is a map of where you are because maps apps don't cache or download automatically. I've installed OSMAnd+ and downloaded a lot of maps to avoid that and I wish Google Maps or Apple Maps made it easier to download a large swath like you can with OSM. (you can even download POI to still be able to do some searching for places if you don't have an actual address)

As for infrastructure I think Verizon is doing something similar with Starlink and there are multiple possible satellite constellations that could be connected too Apple is just the first to include what I think has to be a new radio or radio component.