Interesting take. To me, he saw the cars go by, sirens blazing, and really realized that he was never going to see the street action ever again. He took out the gun, made everyone think he’s contemplating pulling a “Shane,” then chuckled and put the gun away as he walked off, as if to say, “It doesn’t matter. I’m free. I made it.”
Yeah, I see that too. In the end, I think that’s the way the writers wanted it-—a non-ending.