This is a hypothetical in this situation, car manufacturers are under no such obligation. Also, rules like this tend to get reversed once the true risk is realized- people dying that is. We do all kinds of things for very marginal improvements to security these days

Well, my comment was from owner's side. An end-user corporation is the owner of a corporate device like car, so it can decide whether turning it on or off. I just commented that for any serious corporation auto-updates will be turned on, per compliance requirements applied to the corporation.