I think I already addressed your first paragraph pretty well in my comment.

If you’re touting something as an alternative to the Global Positioning System, I think it’s reasonable to expect that it’s going to cover at least most of the globe.

It also doesn’t really seem like it’s intended to be an alternative, more like an extension or backup to GPS. If I available you should still be using GPS, this is just something you’d fall back on if regular GPS goes offline. Sort of like how you wouldn’t want to run your house off a generator 24/7/365, but if a tree falls on the power lines by your house you at least have the generator to keep your fridge running.