I think the durability of the sedan as well as its worldwide appeal argues well for it as a concept that resonates with people's ideas about how their lives are oriented. They understand the difference between an area for powertrain, an area for people, and an area for their stuff.
In Europe, you would almost never have people with large amounts of income being happy with a two-volume vehicle like a hatchback or a minivan. They want to structurally show their societal position, which is why three volumes are so popular. They show 'I'm part of that hierarchy.'