Bogus…I had a good friend who would keep his cars till they absolutely rotted. He was working on his third divorce along with the expensive property loss that went with it. I sat him down and explained to him, that cars compared to marriages are cheap. He just needed change in his life. He then decided to remarry his third wife to which they remained for the next 25 years until he passed away. During that time with both his wife and he having their own car, he traded cars very 18 months, trying out every car he ever dreamed about owning, but finding it much cheaper then divorcing wives and buying houses.
So, in my very humble opinion, people do what they can afford or get away with. My wife and I have been married for 44 years but I would trade cars every 3 to 5 years if I could afford it. Family expenses kept my average ownership to ten year mark.