They still sell high-end luxury cars with big margins.
The dealers and car makers make out if you get expensive add-ons like heated seats, sunroofs, and doo-dads.
What killed the big gas hogs was emission and mileage standards.
Personal luxury refers to the fact it only had two doors. Very few cars on the road now have two doors, but in the 70's and early 80's they were very common. Think Thunderbird, Monte Carlo, Eldorado, Mark V, Chrysler Cordoba, Rivera, Toronodo, Regal, Cutlass.... They were a dime a dozen. They were all very lucrative with the most expensive Cadillac and Lincoln always being the Eldorado and Mark. If the big three had their way the personal luxury car fad would have gone on forever. People want four door crossovers now. If it doesn't have four doors people don't want to know about it.
It all started with the Thunderbird, followed by the Rivera.