Probably something along the lines of: Without accommodation, being able to learn, participate, and demonstrate competency in a series of courses which presume a student's mastery of information presented through secondary education.
Ok. If we take that definition, is there any reason a test shouldn't consider whether a student had a very good school and learned half of what they were given, or a very poor school and learned everything they were exposed to? (a contrived case, of course)
I suspect your question has an unmarked asterisk, which is that the students end up with similar standardized test scores and GPA. For that to happen, it must be the case that a student at the good school can get good grades while learning only half the material, which seems not possible.
And so the answer is that colleges already can and should take into account % learning through GPA.
Yes similar test scores, for the GPA it might depend on how much we trust the scoring from the good school.
I was imagining that the good school presented more and better information, (perhaps more at the style and pacing of a good college classroom,) While the poor school may not have even presented all the information, or done so in a rushed way. (Focusing on that majority of students bound for community college.)
Big difference.