Earlier quoted context omitted.
> The trauma is a consequence of poverty and bad parenting which is because of low IQ You have the primary direction of causality between trauma and IQ reversed. https://scholar.google.com/scholar?q=childhood+trauma+and+IQ... Population scale trauma exposure and bad parenting is a result of poverty, social structures, and sometimes wars and conflicts, not something predetermined by genetics.
The IQs of adopted children have next to nothing to do with their environments, and much more to do with the IQs of their birth parents. IQ in general is very strongly heritable. There are several adoption and twin studies that have demonstrated this effect, e.g.: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8513766/
Regarding race/ethnicity correlations from the paper you posted:
"(McGue et al., 2007; Miller et al., 2012). McGue et al. (2007) reported minimal ethnicity effects in the SIBS sample at intake, which we largely replicate in the current follow-up assessment. While rearing family socioeconomic status and polygenic scores were both moderately higher among Asian offspring (Cohen’s = d .36–.46; p Also, the children in that study have not been victims of trauma (or the study has not considered and controlled for it), so it says nothing about that factor in eventual IQ of the individuals studied.