But the point I'm making is there is a land based system that functions well enough and so satellites aren't necessary.
The point you're missing is that "land" is the operative word. What if you don't have any land (Like way out at sea) and you need your location? Today, you use GPS, not the other two land-based methods, as there is no land.
Anecdote: My wife was crewing on a 44' sailboat from Los Angeles to French Polynesia and back. On the way back, they were trying to thread between two storms and tore their mainsail. She called me on their Sat Phone (Expensive call) and she gave me their coordinates she got off their GPS - They were 1900 or so miles south of Hawaii, about here (red dot):
There were no cell towers or wifi connections anywhere even remotely near them. (They were able to limp to Oahu with just a semi-functioning mainsail, a jib and motoring)