I disagree. Education boosts IQ scores by 1-5 points [1], where 1 standard deviation from the mean IQ score is +/-15 points. The spread on cognitive abilities is clearly broader than education can cover.
Education has improved the average IQ of multiple East Asian countries by 15 points over two decades. That's an entire standard deviation improvement for the whole population. One-on-one tutoring has been shown to make a two standard deviation difference. That's the difference between median intelligence and genius. https://en.wikipedia.org/wiki/Bloom%27s_2_sigma_problem
Your study is about the effect of an extra year of badly done education on people who drop out of school, which is worth 1 IQ point. That same study shows that the effect of mediocre education on people who don't drop out of school is an increase of 5 IQ points.
[1] https://pubmed.ncbi.nlm.nih.gov/29911926/