Is one of the film's messages is that...
... many if not all people form their official de-facto personalities and traits since childhood, and that, like in the George case for instance, if you lied and bullied someone seriously in childhood, you are likely to continue to have such characteristics in your adult life tens of years later. Correct?
Granted, some people CAN and even DO change, yes. We also hold adults for many obvious (and some less so, at least on first count) reasons to a higher level of accountability and responsibility for their deeds than children, but most of them form their personality in childhood years, correct?
So if you were mostly mean as naughty as a child, you are likely to continue to act in similar and possibly worse ways as an adult, yes? And this is at least partially what the movie is about and how the conflict between George and Majid started in childhood and escalated into something more serious and sinister in their adult years, agree?
I thought so!