No, people can create their own "the line."
I just realized they did this in Solar Opposites. It was "the wall"
No, its autonomous "colonies." Many shows went over this, and those shows got canned because people are responding negatively.
There were two shows I especially liked, despite the negative connotation, those shows are "Corporation" and "Incorporated." These shows talk about these bordered "walls" between communities. For example, California has an express lane from 'a' to 'b' to be for the rich, people who can pay, people who have connections, etc. While the rest of the state is like 3rd world, socialist donbasses. So criminals are more respected, more like welfare states. You want drugs, find a criminal. You want sex? Find a strip club with no rules. It was a great show, it was world building right in your face, but all these people reacted indifferent.