I wonder what the extremely rich do to get a car that isn’t a security risk? I’ve heard you can throw money at high end car dealerships to disable spying, but I wonder what the internal process is.

It's easier than that, you can remove the cellular modem. Dealers won't generally accept to make this mod, but any independent shop should be able to. There are also plenty of videos on YT to DIY.

This will probably be a thing, but it's not clear that folks are cognizant of the risks yet.

I haven't heard this. Do you have any examples?