It was never billed as a 'sports car' anyway. In fact, it was originally meant to be an economical, fun car.
It was a new class of car that came to be known as the 'ponycar' which gave birth to copycats like the camaro/firebird 2.5 years later.
Sports cars have seating for 2, like your namesake, the corvette.
Of course if you wanted some REAL horsepower in 1965, in a sports car platform, you would've needed to buy a Cobra.
OOH. Thanks for the education. (Saving all those back issues of Motor Trend sure comes in handy, huh?) However, some of your "facts" require correction.
1. "In fact" the Mustang was "meant to be" a way to get suckers to buy a piece of junk Falcon by putting a "sporty" body on top.
2. The ponycar breed didn't begin to improve until Chevy/Pontiac jumped in and forced the blue oval guys to evolve the Mustang into some semblance of a performance car.
3. Every Mustang guy I run into considers his car a sports car (hence, make-believe sports car).
4. I guess the Porsche 911 (4 seats) and McLaren F1 (3 seats) aren't sports cars. (Please, let's not get into the whole "GT Car" nonsense either.)
5. Cobras were powered by Ford, but they certainly weren't Fords. You certainly couldn't just go to your local Ford dealer and buy one off the floor. And the engine got a lot of help from Carroll and the boys before it went in.
6. If you want to talk about REAL HORSEPOWER, the street version of the Cobra's small block 289 had 271 horsepower while the big block 427 had 425. The '65 Vette had several engine options, but the big block 396 also put out 425 bhp and the top of the line small block 327 put out an amazing 360 horses.
GAME OVER