But the thing is that you don't have to be a student from a branded school to have this characteristics. Everyone has the capacity to do well, it's just whether they give up easily or not. Instead of looking at in-born intellectual abilities, I think it's more fruitful to look at after-born characteristics of persistence, determination and grit. These are the attributes that can be cultivated. And everyone can do that, students from branded schools or not.
Between a smart but lazy person, versus an average but hardworking person, I'll bet my money on the latter. Hardwork and persistence triumphs everything, eventually.