Cars collect a startling amount of data about you
https://www.bbc.com/future/article/20260513-your-car-is-spying-on-you-its-about-to-get-worseOlder cars may not have cellular data, and some new cars (e.g. the Slate electric car) may be specifically designed without cellular connections or with easily removable chips, but so much can still be inferred from omnipresent roadside surveillance.
It's not enough even to have private cars. The solution must be legislation that limits all of: data collected by cars and cameras, data shared among third parties, and placement of cameras without informed, specific, continuing public consent.
And every time flock-style cameras "could have" done some good, the surveillance state's cheerleaders will beat their drums and bleat their demands.
Roslin: I heard you're one of those people. You're actually afraid of computers.
Adama: No, there are many computers on this ship. But they're not networked.
Roslin: A computerized network would simply make it faster and easier for the teachers to be able to teach-
Adama: Let me explain something to you. Many good men and women lost their lives aboard this ship because someone wanted a faster computer to make life easier. I'm sorry that I'm inconveniencing you or the teachers, but I will not allow a networked computerized system to be placed on this ship while I'm in command. Is that clear?
Roslin: Yes, sir.
Adama: Thank you. 'Scuse me.
At least in the EU it’s quite illegal and even if a car maker slips something in, GDPR is always there so one can request a copy and have it deleted. Wish the regulation was even stricter though.