Certainly it all varies location to location. I'm unaware of a regulation like you suggest in CA, and don't believe there is one - where did you grow up?
It's certainly the case that it's better and safer to ride (or drive) where you have space to stop, and that that should be preferred when picking a route or building a road, but other concerns can sometimes wind up dominating.
Maryland. The law may have changed or I might be wrong about it. They used to not require helmets either. Growing up we used to get all kinds of community safety advice from the local schools and safe biking was a big push. I don't know that a similar "safe driving around bikers" ever happened though.
It's certainly the case that it's better and safer to ride (or drive) where you have space to stop, and that that should be preferred when picking a route or building a road, but other concerns can sometimes wind up dominating.