Read the act[1]. It's targeting modifications like ripping the baffles out of motorcycle exhaust or having open headers. I had a friend back in college that did this to a street motorcycle and it was audible for over 3 miles at night in the suburbs, absolutely absurdly loud.
Rusted out exhaust pipes from road salt in NYC on cars will make them louder but nothing like what I'm describing. Basically makes them have an annoying low pitched rumble similar to what those stupid $40 ricer 'fart can' modifications would. Few orders of magnitude of a difference between loudness.
I have a "noisy" unmodified car, and my neighbour has an Abarth with a modified exhaust. I haven't measured the noise difference for an exact number, but I'd wager his car is about 15x louder than mine. _No_ old unmodified cars are going to be caught by any laws that are aiming to capture nuisance laws.
Rusted out exhaust pipes from road salt in NYC on cars will make them louder but nothing like what I'm describing. Basically makes them have an annoying low pitched rumble similar to what those stupid $40 ricer 'fart can' modifications would. Few orders of magnitude of a difference between loudness.
[1] https://legislation.nysenate.gov/pdf/bills/2021/S784B