I’m not debating there is a hereditary component to intelligence - though I think you’re wildly off the mark in stating it’s up to 80%.
This: https://ghr.nlm.nih.gov/primer/traits/intelligence says it’s 50%
This source: https://www.scientificamerican.com/article/is-intelligence-hereditary/ says “Genes make a substantial difference, but they are not the whole story. They account for about half of all differences in intelligence among people”
This study https://www.nature.com/articles/ng.3869 on the other hand concluded that up to 4.8% (not 48%, just 4.8%) of the differences between study cohorts could be attributed to genetic factors.
And this study https://www.nature.com/articles/ng.3285 points out that twins, in fact, do NOT have closely linked intelligence traits.
What I’m saying is that IQ is not a particularly good measure of intelligence, and no study which only relies on it as evidence of intelligence is a quality study. Anyone who claims to be ‘smart’ based on their IQ alone hasn’t investigated the question of what IQ is measuring.
Your article actually supports me more than it does you. It cites an article and seems to misquote it. It stated that 50% of intelligence is from genes. The article it links to only says "the percentage of the variation in intelligence accounted for by genetic causes is usually given at about 50%." In other words, this is just a common estimate, and the possibility that scientists expect to find even more genes related to intelligence is left open. It then states: "Heritability estimates for young children are typically lower, whereas estimates for adults are higher (up to 70–80%)." There's my 80%. The article also mentions adoption and twins studies, which supports me, as well as stating that IQ tests are generally stable from childhood to adulthood: "For example, when the same intelligence test is taken at age 11 years and repeated at almost 80, about half of the variance is stable."
Which is a big problem for the "Education and wealth determines IQ," though the article admittedly suggests that there is a correlation between wealth and IQ (but the real correlation is that smart people tend to get high paying jobs, not that they have better access to education or food that gives them a high IQ score).
https://www.sciencedirect.com/science/article/pii/S0960982213008440