What's so great about Escape from New York (1981)?

If it wasn't for EFNY, we wouldn't have this

The ultimatum that Snake is offered has an extra punch due to the device injected into Snake that will kill him if he doesn't complete the mission. And it is the President he is trying to rescue, it is not the President who offers him the mission. The movie also works due to a performance by Kurt Russell that blew his accustomed screen parsona to pieces forever and was really the beginning of career renaissance for Russell that no one saw coming.