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Not at all. I don’t have expertise in this topic so I’m not in a position to make a point (your take is very low IQ btw). The economist Thomas Sowell argued that government policies like affirmative action misplaced students and turned them into academic failures whereas they could have succeeded at a different college. He has written a few books about the topic as well as his own journey through the US education system.
A testable hypothesis could be that socioeconomic status has become an increasingly strong predictor of GPA disparity over time and that it interacts more strongly with race and/or gender over time. The interaction means that the effect of socioeconomic status is amplified by race/gender-based policies. This model assumes all schools are inflating their grades at the same rate but this assumption can be relaxed. It assumes that affirmative action policies are more widespread at public colleges and that private colleges are more selective in who they admit (this could also be modeled for individual colleges if AA policy could somehow be quantified).
More meritocratic policies should be better at placing students into institutions that are better matched to their ability. For example, a state college that has to admit the top 10% from each high school in a state would be more likely to misplace students than a private college that is free to pick from the top 10% of students across the whole state and, due to their parents higher income, probably also went to better high schools. Students who fall behind also reduce the quality of the education received by other students, thereby exacerbating the GPA underperformance while increasing the cost of education.