SAT scores would be positively correlated with success even if they were entirely random as long as universities continued to use them as a factor in admissions. It's sort of a corollary of Goodhart's law that it is difficult to assess the quality of a measure while it is being used as a target.

I’m not disputing that these tests measure something, they obviously do. However what they are measuring is not what most people consider a satisfactory definition of intelligence. In fact most psychometricians simply give up and define intelligence based on what these tests measure (i.e. operation definition). Without justification that is very poor science.