Yes, intelligence is 100% environmental and cultural factor, that’s why genetic affliction such as the Down syndrome has absolutely no effect whatsoever on the subject intelligence... It’s incredible how far some people will bury their head from evidences because of their ideological beliefs.

On the contrary, when some facts put a positive light on certain groups (for instance the better maximal physical performance) there is magically no taboo about it at all, and no pressure groups asking for "affirmation action".