Im a north carolina state inspector and that is not true. What ever emission equipment the car came with from the factory it has to have for inspection. Its just a visual inspection so if you could fine somebody to just slap a sticker on it you would be fine.
While all emissions equipment is technically required to be present, the inspectors are not allowed to pop the hood. You could coyote swap your car and they probably wouldn't know. I've always had some equipment deleted and it's never been an issue because they can't pop the hood and see it.
All most inspectors care about is the usual BS like lights, wipers and tires. Most are fine with loud exhausts, but if you don't have cats they will send you on your way. That's the one thing they've always cared about because they could get in hot water if they get caught letting catless cars through.
Yup. The laws are already there and have been for a long time. Cats and emissions are federally required. The states just are jus enforcing differently.