Having read many of the comments below, it seems to me that every American (and non-American) has different views on what constitutes a "muscle car", a "sports car", and even a "pony car".
I know someone who considers anything made past like 1973/74 to not be considered muscle cars, but rather sports cars. Admittedly he's not a huge car person. Personally, I consider just about ANYthing with a 5.0L+ engine to be a muscle car, and ESPECIALLY 6.0L+, and all muscle cars need to be 8 cylinders with no exceptions (other than the very rare occasional turbo 4 or 6 limited edition cult classic from the 1980s, like SVO Mustang, 20th Anniversary Trans Am, or GNX Regal).
Of course muscle cars need RWD. Having the front wheels spin means it's not a muscle car, for two very different reasons: AWD will pull instant torque (akin to an electric or rally car), and FWD cannot handle more than 350 hp in most cases (as most FWDs tend to be economy cars or hot hatches).
With that being said, I wouldn't necessarily consider cars like the M3 E92, C63 AMG C204, or GranTurismo M145 to be "muscle cars". True, they have naturally aspirated V8s, RWD, two doors, came out in the late 2000s and early 2010s (around the same time as the revival of the "true" muscle car). They're also inexpensive to buy these days and around the same value as a Boss 302 Mustang, a Shelby GT500, a Camaro SS 1LE, a Camaro ZL1, or a Challenger SRT8. But they are far more expensive to repair. And most importantly, BMW, Mercedes and Maserati ALREADY ARE associated with "fast/snobby" even as brands themselves.
I agree with one commenter that a muscle car cannot start off as a sports (or luxury) car. The only exceptions to the rule are the AMC AMX (a sports car, but based on the Javelin pony car) and the Cadillac CTS-V/CT5-V Blackwing (a "luxury" car, but always has been cheaper than competitors from the start AND based on a variant of the Holden Commodore/Chevrolet Camaro chassis).
Also, because Cadillac (and Lincoln too) DO have a history of slapping unusually BIG-displacement engines into unassuming non-performance-oriented cars, AND that their status as "old man's cars" differs them from the "snobby/(young) bad boy" association of most of the European brands, it might as well be easier to call their cars muscle cars. Albeit they are a little too big to be classified as such (especially those from the 1960s and early '70s).
Cadillac has V-Series and Blackwing models. Lincoln has Grand Touring PHEV models. All three are absolutely a good start to appeal to youthful enthusiastic buyers. But they're still not the snobby machines a gold-digging Tinder or Bumble girl might associate with.