The linked paper in #752 does NOT show college selectivity has any effect. However, I wouldn’t be surprised in a refined study where school selectivity is well-defined with fewer college majors included the authors find Ivy/elite schools are better as claimed in the OP. What sticks out the most in the study is that how much one makes 10 years after graduation has 80+% to do with something not examined.
I’d like to see a study like this for college admissions that may contribute 80+% influences to things other than test scores, GPA, EC etc.