Ten Million Mile Club
There are so many things about this scene that sell me on it. Ryan has been talking this moment for most of the movie, and everybody just sort of stares at him and says "Really?"
Abrupt turns happen, and Ryan is at his lowest when he passes his goal. It's exactly as empty as everyone knew it would be (though he gets to talk to Sam Elliott, so surely that should temper the blow a bit).
Worthless goal achieved, he sends his just-married sister a massive number of his precious miles. It's bittersweet, though. He does something nice for a change, but his own life is still completely untethered at the very end of the movie.
Weirdly, no clips seem to exist for this. Instead, here's a clip of him explaining his goal.