My first thought as an easy fix for this was similar to what you are suggesting - I was thinking to be truly qualified as a manager you need to have at least 1

My first thought as an easy fix for this was similar to what you are suggesting - I was thinking to be truly qualified as a manager you need to have at least 1 or 2 direct reports over a certain period of time or else you don’t qualify. I think in practice that is essentially almost the same as the ratio requirement you are talking about.