If you are looking for outliers you are missing the point. Just because two things are correlated doesn’t mean that there is a causal relation. These studies may be thorough but they all have failed to show an actual causal connection. Assuming that there is one based only on correlative evidence is just faulty logic and bad science.

The classic example is that both ice cream sales and crime increase in the months June through August. This doesn’t mean we should conclude that ice cream causes crime or that crime induces ice cream sales. No because while these things have a correlation neither causes the other. No, instead we must look for an actual causal relation in this case they are both induced by warm weather.

The same goes here while there may be a correlation between company success and DEI there no evidence to support a causal relationship. No, in fact it’s far more likely that this is simply a matter of better run companies are both more successful and more likely to initiate DEI programs. But you cannot attribute business success to DEI without evidence of an actual causal relationship no more than you could take a badly managed failing company and make it successful by implementing DEI programs. Because again there is no evidence that the two things are related in this way.