Further, the heritability of potential for high IQ isn't really in question. Put another way, it looks like environment can severely diminish the IQ of a potential high IQ child, but it can't probably can't severely raise the IQ of a child born to low IQ parents.
What is heritable is the potential. Environment determines, to an extent, how fulfilled that potential ends up being. This is why smart kids can study and increase their IQ test scores.
Perhaps my thinking is wrong or on the extreme end of the scale, but I would argue that we can extrapolate that environmental factors are a much more important factor than genetics considering various environment factors can affect genetics to certain degrees and your genes mean little to nothing in the worst environments -- only beneficial in the right environments.
Also, if you’re hanging out with people who talk about genetic IQ all the time you should really get a better hobby.