I don't think they'd all succeed, but all well prepared college students don't succeed. I think they'd have a harder time than an "average" student because at least they can't fall back on their parents for as much experience based advice or money.
I don't know what universities should use other than test scores. But I do want them to do more.
I assume the answer is greater than 0% and less than 100%. In which case, the second question is, what signal other than test scores could the top 10 universities use to accurately distinguish between those in your particular cohort who would most likely succeed and those who wouldn't?