I think your is statement is inaccurate to the point of being intentionally misleading:

Many devices, when running, and in some cases even if turned off but connected to their battery, will ping cell towers (maybe even BLE/Wifi) and get triangulated by the network infrastructure (such as cell towers) without actively broadcasting the GPS location.

That's why I don't quite understand why the gubernment needs to have finer grained data (esp around the US/Mexican border). Precision location info would only be needed if you need to track people in densely populated areas.

That location information is not available to apps or ad networks. The government can get access to that data from the carrier with a warrant, but that's not what we're discussing here.