Could someone who read it more attnetively tell me, by this methodology, -> If in retrospect YC finds any factor that its selected founders who turn into unic

Could someone who read it more attnetively tell me, by this methodology, -> If in retrospect YC finds any factor that its selected founders who turn into unicorns ($1b, $10b etc) have in common (more than its non-unicorn, also accepted founders) -> Then by this method, could it conclude retroactively that it had been "biased" against that factor? (since it is present more than in its non-unicorns whom it had also admitted; i.e. in other words, those with the factor are more performant than "would be expected" without the bias against it?) Or have I misunderstood?