OnStar reports location and speed data to the car manufacturer. Sometimes they will sell this data to insurance companies to raise your premium, as several news stores pointed out a few weeks ago. I couldn't really find an advantage to OnStar, (I have my phone to call emergency services) so I disabled it by pulling it's fuse.
For my 2019 bolt, it's f31 in the instrument panel fuse box, just down and to the left of the steering wheel. The fuse box cover comes off when you pull it hard from the bottom.
I was able to find which fuse went to OnStar in the owners manual and labeled on the inside of the fuse box cover. You should be able to find it for your model car there too if it uses OnStar.
I did have the casualty of my speaker for calls and texts. I'm not able to use it right now. I'll see if I can dig in and reconnect it somehow, but we'll see.
Who knows that other into they're snitching back to GM, or what they could do in the future, so I recommend disconnecting it. Good luck!
The thing even some reporters who’re alarmed at this story like: usage-based insurance which does actually let people pay less if they’re provably safe. Safe, and/or low mileage. They also want drivers to be alerted when aggressive driving is detected to be given a chance to improve.
I think a program like that might be OK today for those who are very well informed about it. One day if every new car is web connected, I can imagine insurers trying to gouge anyone not in a driver monitoring program.
Such a privacy & liberty nightmare has a small silver lining I almost refuse to acknowledge: in a full-on Big Brother driving world, with human-expert-equivalent analysis of behavior, raging murderous drivers would certainly find it harder to do 100+ MPH with their lights off entering an active crosswalk while passing a schoolbus in the rain.