I agree. The guy will probably get off and hopefully won't have to sue to get his guns and truck back.
The downside is that the unconstitutional law will stand to trap somebody else.
Even if the guy expressed an intention to stop at the airport, he was free to change that intention at any time and proceed to the range without making any such stop. The authorities stopped him BEFORE he had broken any law and are attempting to jail him on a felony and remove his right to keep and bear arms for life. If these people were on fire I wouldn't spit on them for fear of putting out the fire.
Well stated.
I would also ask how 'stop' is defined. Typically, it would not include instances where, although the vehicle is motionless, the driver remains seated with the belt fastened and the engine running.