Phones also use WiFi access points and some Bluetooth beacons to get a better location. AFAIK only Google and Apple have up-to-date maps of these that are useful for navigation, and no one else does (Mozilla threw the towel a year or two ago).

Cars can theoretically have better GPS antennae, and can do better dead reckoning using wheel position and wheel rotation speed. But do they? I haven’t seen any evidence that any car actually does better than a modern phone.

Especially inside a dense city, WiFi location can be much more precise than GPS.