I haven't seen a single car since the wipe.
170 skill is enough for anyone to steal car in 3 attempts.
That sounds very easy, but you forgot that 3 attempts = 30 minutes. Car lockpicking have higher timeout than lockpicking a trunk/door/container.
Dunno how about cars but caravan cooldown for trunk is 2 mins and for caravan itself its i believe around 4? dunno exactly but its 10-15 minute job when you are really lame. And how long does people stay at mining sites?