If you’re suggesting that having “a shitty home life” can make people perform badly on tests, but not perform badly in real world tasks, we don’t “know” that. It’s something people want to be true, but there’s not much evidence for it. Meanwhile, there’s reams of evidence that standardized tests scores are highly predictive of performance.

Most people don’t go to Oxford just to go right back home to said shitty home life.