I think it comes from the Neon being designed originally not as a sports car but as a economy car that was later turned into a sports car. It is stuck with the stigma of being a Econo-box trying to be something else. How many years was the Neon in production before the SRT-4 came out? after that long you just associate it with being an economy car.
with the Lancer you could get the Evo at the same time so it was associated with being a sports car.
The Mustang was originally a sports car and has always been one, except the Mustang II era everyone has turned a blind eye to those.
The F-body has always been a sports car even though they tend to carry the redneck stigma of the Mullet mobiles
A 6 cyl Mustang is still a sports car (although under powered) the same goes for a 6 cyl F-body.
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