Sugar - I'm confused about what your point is.
Are you denying the scientific conclusion that intelligence is strongly heritable?
There is still some debate about whether the genetic factor affecting variation in intelligence is nearer to 50% or 70% but there is no serious dispute that variation in intelligence is significantly genetic.
Of course it goes without saying that a person with a genetic gift for high intelligence won't flourish without a suitable environment - 'nature via nurture' as Matt Ridley expresses it.
Just as an individual with the combination of genes for higher than average height won't achieve that potential without proper nutrition. On the other hand no amount of protein will cause somebody with the genes for less than average height to grow to 6' 4".
IQ tests are not perfect but they are very good, and if you research the literature you will find that scientists go out their way to compensate for social factors when measuring groups. The commonly high IQ of Asian kids is not explained by pushy parents.