If there were notable positive effects, it would likely be danced around, because saying positive things about the groups with Neanderthal admixture is a touchy subject.
Is research on the subject tabooed and not encouraged ?
You didn't answer: is that vetoed in public research program or is it the media or the philosophy undergrad who don't know how to deal with the subject and thus avoid it ?
Of course, east asians and specifically melanesians have probably the most neanderthal DNA, maybe twice the amount of the average European, and I would love to hear a white supremacist argue for the genetic supremacy of Melanesians.