Assuming your car has all the functions you care about, and the OTA updates aren't bringing you any bugfixes or feature updates you care about, is there any good reason to update? Or even have it online to begin with? I'm not expecting someone to hack my car; on the contrary, I'd rather have it be impossible for the automaker to reach my car in any way without it being obvious to me (i.e. me flipping a switch to get it online for whatever reason).