Street legal doesn’t mean incapable of violating noise regulations if misused just like speed laws or any other traffic laws. Most gas engine cars can produce extreme amounts of noise just not when used as intended for driving on streets.
This is true, but why not fine all individuals in that case (assuming the driver was not accruing in bad faith).
Government regulation has to apply equally to the rich and the poor and if there was no signage indicating his street legal car could not be used on that street, it’s hard to see how he should be liable.
I don’t have a lot of sympathy for a guy with that kind of money, but it doesn’t mean he’s filthy rich either, for all we know he’s got cancer and sold his house for the dream car, who knows.
The point is, government regulation should be consistent and act in the best interest of the people. This is a failure in public policy.