I think the problem arises due to a very small portion of society that take it too far. The association between nudity and savagery has been grandfathered in. Even if the nudity is pure, people are explicitly or unintentionally afraid, and for good reason: we have children and death in porn. No reasonable person wants that, so we restrict the lot. ML probably could solve this specific problem, but we are too afraid to loosen the borders.