Would the sandbox mode in grapheneOS make a difference? I don't have it, I just read that the sandbox mode is used for Google Play Store, can you put anything in a sandbox?
Modern cars regardless of fuel here in North America are the same deal. GPS location, speed, throttle application, miles, metrics etc. all being sent to the mothership with privacy, authoritarian, insurance, etc. implications. Toyota has the option to send it to your insurance company. (but please do not do that)
There are many ways to work around it ranging from pulling fuses, wiring, opting-out, to getting an older car either without any cellular functionality or on a 3G network that’s been shut down.
Sadly you’ll have to search any model you’re interested in. And it’ll vary between model years as well. And perhaps most annoyingly you’ll need to deal with the “you have a phone just submit to more data collection lol” clowns.
Best option is probably the opt-out - I mention Toyota a lot but they do have a red sticker talking about how to opt-out.