At the very least, their vehicles (mine at least) require you to opt-in if you want data harvesting.

For Mercedes’ app, the privacy policy outlines everything that needs to be shared with them for its functionality and then anonymized telemetry is opt-in, rather than opt-out. I didn’t opt in because even if it’s anonymized, I don’t need anybody knowing certain things, like how fast I drive. Also it explicitly stated that if you opt into the telemetry, you “have to inform anyone who borrows your vehicle that anonymized data is being collected”. I appreciate that, it’s a lot more transparent than most companies are.