Colleges can already access this information in other ways. This is just a proprietary weighing of these things into one number. Given the information the SAT has access to, the number seems likely to be based around the student's address and school, rather than unique challenges to that student, like how present parents are in the student's life and if they have to care for younger siblings or need a part time job to help out. I don't remember having to give the SAT any sort of income or family data, but that sort of thing would be equally, if not more, relevant to the discussion of experienced adversity.
Just because a school has access to the information doesn't mean they have the expertise, time, or money, to turn that information into a number that can then be used in admissions. Admissions tests have existed for centuries the idea of the SAT is by having a single standard you can have one group of people make a better test for less money (and student time). This is very much the same thing, figuring out how to rank high schools and estimate adversity by street address for the whole nation is a HARD problem.
