In the moderately selective range that CSU applicants and admits mostly populate, there is enough differentiation between applicants based on easily calculated academic criteria that the CSUs are mostly not concerned with trying to differentiate between an overabundance of applicants pressed up against the top of the scales. Adding consideration of subjectively graded criteria like extracurriculars, essays, etc. would add considerable amounts of work in the admission office for only minimal changes in who gets admitted at the margins, assuming that academic criteria remain the most important factors.