the fact that in 1973 Sam is in a situation where he isn't in control, and where the most fundamental certainties have crumbled - including a lot of false certainties about himself that he's been using to shield himself from other people and the world in general. It's not the magical rightness of Gene, it's the whole am-I-dead/dying/insane/back-in-time thing that makes 1973!Sam more likeable (even to himself) than 2006!Sam.