I’m not sure why this shocks people. It’s definitely not new or tesla specific.

Does your car have an app that let’s you see data from your car or do anything to remotely control it like unlock the doors? then that can be done by the car company that runs the backend the app communicates with.

It’s also not limited to app based things, cars have had this since OnStar was a thing. It’s just much more obvious these days.

just say I help improve ad blockers on YouTube and refuse to elaborate.

They don’t provide stuff for free, they provide stuff in exchange for your data and to sell ads.