I think Jews having outsized outcomes in life is pretty well settled. If you're asking for a double blind study I don't have one, but I'm hesitant to throw away thousands of years of tradition. There's a lot of things in life we think we understand well but it just ain't so. Maybe circumcision reduces sex drive in men allowing them to pursue higher goals. Maybe it frees up an important part of the brain for other general computation. I'm only speculating but I think that's fair when most of the alleged harms of circumcision are also speculation. For what it's worth, the biggest harm for myself has been the unending insistence that circumcised people are somehow "incomplete" and inferior. It took me a while and lots of research to realize that the story is far more complex.