It is a vaguely-written law, and no one can be sure exactly how a court would interpret it. It could be argued that it is intended to disallow inspection/disarmament unless there is RS that a crime is being committed involving THE GUN. It could be argued that it is just restating the current Supreme Court precedent on searches and seizures. Or it could be seen as just making sure that the SDA isn't ever interpreted as specifically granting police authority to inspect any firearm carried pursuant to the license during any traffic stop, which is the way some states' carry laws are.
Just under Supreme Court precedent, the warrantless seizure of property can only occur in a limited set of circumstances. In the case of a gun, it would typically be justified as a Terry search, which requires reasonable articulable suspicion that you are both armed (which is a gimme in this case) and dangerous (which is not met unless supported by reasonable suspicion, based on specific and articulable facts, that you are, which typically isn't present for a normal traffic stop).
