Wrong. The author stereotypically defines the wealthy. First of all, most of the wealthy live modestly and in normal homes. Second of all, it's their money. None of the author's business what people live in or what they buy.
No. Let me change the situation. Is it good to own a ford escort when there are no roads to drive it on or own a ford escort when there is a road system to ride it on. His argument is not dependent on a particular definition of wealth.