The name "muscle car" comes from the 60s when this type of car really was a "muscle" car - in that the NA makers took an inexpensive basic mid-size car, cut out any frills, and stuffed the biggest V8 they had into the engine compartment. Some of those cars didn't have radios, heaters, a/c, or electric anything. I seem to recall one of them didn't even have a rear seat (all to reduce weight). They are brutal cars, no refinement, and did not handle in a corner nor stop very well. But they did go like stink in a straight line either for 0-60 or drag racing purposes.
None of today's so-called "muscle cars" are really that at all. The NA makers have made the Mustang, Camaro and Challenger all look like the old ones for sales to mid-aged (mainly) guys who are getting old and are on a nostalgia kick. The name today is really a mis-nomer as today's car are loaded up with all the luxuries and toys available today. They do handle somewhat better than their 60s ancestors, but today's car is not really a muscle car at all. In fact, any 6 cylinder version is not by engine definition, a Hyundai (as good as it is) is not a muscle car either. The V8 versions of the Must/Cam/Chall are the closest you get today to a real muscle car, but are still not really it.
What are they today then? Well, I would suggest they are some cross between a sports car and a GT car. They are definitely "sporty" but maybe not a true sports car either. Additionally, there are some sedans today that can beat these modern muscle cars in a drag race, or on a road track. I have one of those animals, and one "could" argue that an M3 is a "muscle car" in that a big power engine is stuffed into a smaller sedan body (albeit that the suspension, chassis construction, braking systems, etc are far from straight 3 Series stock).
Not sure this proves anything, other than maybe the name "muscle car" should really only apply to the 60s/70s NA V8 powered true muscle cars.
Just thoughts.
