It is not that easy to generalize that people never grow up or discover themselves if they stay within their environment. Some do! for some it might take longer time, as all their needs are met without a lot of struggles.

In my opinion what matters is how much space & freedom do you have to discover yourself & grow, how far are you willing to go to validate your core values, social norms and cultural values. You can have it at home or abroad. You can be at the other side of the world yet you stick to what you only know in life.