The key difference is even loud factory exhaust setups leave room for relatively quiet operation depending on how you drive.
That Elantra driver was an idiot: he went in a town and drove in sport mode and drove in a way that forces extra loud pops
If he hadn't been forcing it the car was perfectly capable of not making excessive noise.
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The $100 bozo special on the other hand has none of that: it's always loud and obnoxious.
In fact it gets more obnoxious at cruising RPM because of drone.
There are aftermarket exhausts that try to match the factory-style "not loud by default", but they're expensive because it takes careful engineering and integrating things like valves and Helmholtz resonators.
I was looking into some kind of fix to wrap around the pipe but instead I had a very good deal on a 13 year old prius fall in my lap so now the civic is parked up while I decide what to do with it.
You can make a car sound excellent with no drone with a $5,000 factory quality upgrade... or you can pay some bozo $100 to cut out your muffler and weld in a straight line pipe.
That may not entitle them, but it represents how people might make this choice without intentionally being a nuance in mind