> [...] who believes he has a theoretically proven approach of using non-randomized observational data to create an asymptotically-efficient unbiased estimator of counterfactual treatments

That would be exceptionally powerful if applied to the social sciences. I've long thought that the extreme lack of statistical rigor in that field has led to all kinds of damaging and biased social policies that negatively affect society, ranging from the legal system to the criminal justice system.