It seems very petty to me.
Brisk is not the only yeshiva that can produce capable, committed, top learners.
My cousin (who did not go to brisk) married the daughter of a rosh kollel. Her father did not look to brisk specifically for a son in law, but to those recommendations of boys with fine middos who were committed to learning. He understood that his daughters future and happiness was not dependent solely on the boy’s level of learning or yeshiva resume but on the person he is.