I didn't have any kids, but I'd liken the "wait him out" treatment to a 2 yr old's tantrum - very strong at first and seeming to last forever, but after a few minutes, the little kid visibly starts having to work up the angst and can't maintain it, eventually giving up. Once the dog learns he'll have to wait to exit the car/boat, etc., and that he'll definitely get to be with his people once he's stopped, he'll change his behavior. After that, consistency is your friend - if you let him out when he's just a "little" excited, just this once, you may start to undo his progress. That goes for other people with whom he might travel/boat.
"What's his name?"
"It doesn't matter."