They will hear the case to prevent New York City from having this ordinance again. Hell, they may even rule any law restricting or INFRINGING on citizens right to be arms shall be illegal.New York has repealed the law
What exactly is the court going to rule on?
keeping it from happening again.
in NYC, and other areas
The Supreme Court does not have jurisdiction over hypotheticals. As the law is no longer in effect, there is no longer an actual case or controversy. This is not the field of this battle. There are plenty of states and cities that have highly restrictive regulations. Pick any one of them and instigate a pro forma case.