If IQ Tests Measure Something Important
If IQ tests measure something important, it's less likely that IQ is mostly genetic. According to Inductivist:
Only 2.8% of Americans with graduate degrees agree with the genetic idea, while 20.2% of high school dropouts do.Since amount of education is strongly correlated to IQ …
On the other hand, speaking as someone with a graduate degree, I suspect that many people with low measured IQs are pretending to be dumb. (If something is easy for us, it might be easy for everybody else.)
This reaction may be common.
On the gripping hand, a belief in inborn explanations of intelligence might make people easily discouraged by the inevitable setbacks in any effort as sustained as post-graduate education.