points for

I wouldn't say they're closer, but their relationship does change dramatically. Amir no longer feels like he's fighting his brother for Baba's attention, and that makes a huge difference as he's always been jealous of their relationship. Amir has also matured, gotten a job, and is now responsible for his father. Yes, they have a completely new relationship, but I think the change is more an effect of Amir's new found maturity than the place they live.