Grit is not unknown in business and has similar problems with hiring. I helped a start up ran by some executives trying to pitch B average state school engineers as they reach senior status significantly faster than more competitive school graduates. HR depts in most tech companies pushed back as they like to hire top school candidates. Similarly as they pivoted to produce advanced hiring processes to recommend these students, HRs refused to lower their days and days of interviews that have low completion rates.

HR is almost always the failure in hiring and I am sure the recruiting/admissions will fight against whatever 'grit' factors and measurement is figured out as they still feel good personally about good grades and test scores.