Where in the world are these road owners, and do they really eve provide this kind of information to mapping companies?

Here in the States, most of the roads are "owned" by the people and our various thousands of governmental jurisdictions do not tell anyone about these kinds of details in any uniform way.

We just kind of figure it out on our own.

That's also where this map would help, it can definitely degrade gracefully. If I know I have two right-hand turns coming, I can take the decision for myself.

This information is all derived from overhead (satellite and aerial) imagery combined with street level imagery (like from Google street view). No road owners required.