It's a mix in the US. "Career" taxi drivers that have been in an area for a long while will generally be able to get you where you want to go based on landmarks and place names. Many will ask for a cross-street and will take you there from memory. Newer drivers or drivers who cover a larger area will rely heavily on satnav.

Even then, many experienced drivers will still use satnav due to changing traffic conditions. Since there are usually several routes that can be taken, using Google Maps or the like will tell the driver what the fastest route is during that particular moment, which might change every 15 minutes.

I remember when Uber was new (black cars only), and the app didn't yet give the ability to enter your destination, the drivers were all very knowledgeable (in SF) and would be able to take me where I wanted to go based on pretty minimal information. Especially in SF, UberX and Lyft Line are full of drivers who don't live in the city, and must rely on satnav to get around. Very occasionally (1 in 100 rides) I'll end up with a driver who has lived in the city for decades and could drive me somewhere in their sleep.