This abstraction might make sense to a fairly bright 10 year old, but actually making the effort to learn is practice for more learning. IQ as an innate quality is highly suspect.
But by the time a person is old enough to be able to overcome their early circumstances and apply themselves to learning, the forces of conditioning, environment and other forms of are already bearing down, since the majority of brain growth takes place before the age of 6.
Can you show us any statistical study of individuals who have "broken the mold"? My guess is that it would be a small percentage. In fact, as many bright parents have found, their own children may not be as bright, since "regression towards the mean" is also a real phenomenon.
The fact that some phenomenon like "a better environment producing better results in one generation" is possible most certainly does not mean it will take place for the majority of immigrants. They will be products of their family life, same as everyone else. Public school and school lunches are certainly not going to be enough. They have never been enough for our present crop of underclass.
Your IQ isn’t something you can ‘learn’. It is there or it isn’t.