>Easier hygiene. We could also cut out all our teeth, so we don't ever get cavities! The problem with the rest of everything you mentioned is that the effect s

>Easier hygiene. We could also cut out all our teeth, so we don't ever get cavities! The problem with the rest of everything you mentioned is that the effect sizes for those things are tiny. Your chance of getting penis cancer when circumcised is 1 in 10,000,000, and if you don't its 1 in 10,005,223. This sort of tiny effect can just come from confounding variables, like "people who circumcise tend to be Jewish and American so they eat better food and get cancer less in general."