So you'll lose the other things if you put it in a Faraday cage.
A cage is a bad way to do it anyway. It's easier to disconnect the cable between the antenna & the telematics module (which has the SIM and control electronics in it). Or disconnect the power to the telematics module. Etc. Depending on the wiring harness style and design of the car's electronics, that may also let you disconnect just the cellular antenna while leaving the GPS/radio antennas connected.
In the future we might see those components getting integrated together... But you can always physically destroy/remove the antenna.
Unless the device itself becomes the antenna or is reacting passively as is the case in RFID.
If you have an automatic toll transponder (ez-pasz, etc.), those things are read very frequently even when you're not going through a toll meter. There's info on this online.
TPMS sensors also transmit a serial number. I wouldn't put it past the NSA to have sensors embedded in certain roads to track that.
And of course, dragnet automatic license plate scanning / tracking is already ubiquitous and there's really not anything you can do about it. Use a bicycle instead, I guess...
Even the coming road taxes are all about constant tracking. How far / which road did you drive? They'll demand the answer. And you put a faraday cage to stop this? Suspicious. The default assumption is going to be fraud. Criminal behavior.
All the EVs will soon enough have some variety of tracking sooner or later. So thats basically all new vehicles. The alternatives will also, whatever they are. Hydrogen?
Transport privacy is likely dead already.