This seems fine if you wanted to use the SAT to measure an outcome for a given level of inputs . If all you actually care about is the actual outcome though, then this doesn't actually help. I guess there could be both use cases for test scores, given that higher education might actually find itself more concerned with showing improvement as an important metric. They might prefer students that show more aptitude for…
Past adversity is in the past. So if someone grew up in a poor environment but you're thinking of admitting them to a good college on full scholarship, they'll soon be progressing at the rate they're capable of without the adversity. So the best predictor of future success in a good environment probably does include a correction for past adversity.
2) There is the assumption that the environment in which you grew up in does not permanently affect the way you learn, while many studies have proven this to be untrue. The most critical years shaping the way you learn is in the younger years. Once you're past that, there is no way you can "make up" for it just by going to a better college.
A radical solution I believe is to completely subsidize all education and child rearing costs, such that every child will at least have the necessary basic conditions needed for them to excel. Of course, parents are always going to try and give their kids an edge, but at some point there'll be diminishing marginal returns. To relieve pressure on governmental funding, another radical idea is to couple this with an upper limit on the number of children you can have, so people will not "overburden" the system by having too many children.