Neurons don't mean shit in isolation; what matters is neural connections (AKA synapses). When you're a tiny baby, first you make a ton of synapses, and then you get rid of a huge number of unused ones and make the most useful synapses efficient and well-connected; this "efficient, well-connected" structure is why you're smarter than a two year old (as opposed to more sensible or knowledgeable).

Think about your brain like a computer: a laptop model having a few percent more space to install a big CPU is okay, but the quality of the code it runs will have vastly more say in how fast the computer actually is.

I too love to throw alley oops to racism by leaving out important context! For example: SAT scores have a positive correlation to exactly the kinds of economic and pre-college educational privilege URM populations have less access to, meaning we should expect fewer high SAT scores in those populations even when assuming the underlying intelligence distributions are identical. Bonus (speculative, but based on a phenomenon that is very well established in easier-to-measure professional contexts): more heterogeneous populations are less prone to groupthink, suggesting that selecting for diversity could actually improve educational outcomes.

And, bonus: by comparing raw percentages of massively different-sized populations, this chart implies that more URM students are being admitted than have the test scores to "back it up" (just look, the middle bar is bigger on the right than the left) despite saying literally nothing about the actual test scores of the actual ORM admittees. Every single minority student at those institutions could be sitting on a 1550+ without changing this chart a whit.

Anyway, I hope and assume that OP was not actually trying to feed the reactionary trolls with this; but looking at some of the other comments here, it's happening anyway.