One of the formative anecdotes in ed reform, experienced personally or second-hand, is the story of a student who is informed by a guidance counselor or other advisor in school that he or she is just "not college material" or shouldn't apply to a top-tier college, or some variation on that theme. Often this is freighted with racism, sexism, class bias or for that matter, just local politics and relationships, and to be clear, these can be very hurtful experiences.
One response to this is to encourage every student, I mean scholar, to aim to attend a selective four year college from the day they arrive at school until they graduate.
On the other hand, the current trending reform meme is the "honesty gap:" that states' low academic standards are misleading kids about how well prepared they are for post-secondary education. This point of view holds that students and parents put a lot of stock on standardized test scores, don't have a lot of other data, and believe that a diploma is a de facto statement of college readiness.
The most obvious way one might double check their readiness for post-secondary education is to ask their teachers or indeed guidance counselor. Some of the time, the adult's honest answer is going to be "No, you aren't ready for that."
Some of the time that is going to be an incorrect answer. Then again some of the time the test is going to give the incorrect answer too. Some of the time they're both going to be biased against women/minorities/poor people.
There's no way to plow through this issue as it is being framed; it is a dead-end approach. The only thing that can be done is to back out and start over, beginning with being clear about what we thought a high school diploma meant traditionally and the implications of changing that. Ultimately though, our systems of college application and induction simply are not rational enough to design our primary and secondary schools around.