Because consumers want, air, PS, no noise, and every other creature comfort known to man, they want the image of a sports car with the luxury and refinement of a luxo barge.
Most people who buy a sports car do it for the image.
In my "sports car world" the standard twins are porky.
Sports cars to me should be RWD, a convertible or coupe, 2 doors, manual transmission and light, under 1200kg at least, with a great power to weight ratio.
Lotus Elise light.
Alfa 4C light.
MX5 light.
Every thing seems to be evolving into fat GT cars.
And everyone is calling fat GT cars sports cars.
The term "sports cars" is thrown around at everything now, so much so it's lossing its true meaning.
Hell, I've heard people call Honda Civics and Golf GTI's sports cars.
The world has gone insane.......