As far as I am aware, most of them aren’t directly transmitting data back to the manufacturer, but the data is stored on the car so if you ever have it worked on the dealership can just pull that shit without consent. I could be wrong though, maybe there are cars now that are doing that. I do know that a a lot of cars are taking the iPhone route of having “encrypted” parts, where if one is missing or replaced, the car just won’t work.