When I worked "behind the gates" in Rolling Hills CA. (millionaire country) I was amazed to see so many run of the mill cars parked in the driveway.
As has been said I think at some point of achievement the need to impress diminishes.
That and some people just don't give a fuch about cars.
My dad had a very successful HVAC business and still owns a few commercial rental properties he bought back in the seventies plus a house he bought with an ocean view in S. Cal back in the sixties, needless to say he has done rather well.
He loves Corvettes... he drives a Dodge pickup.