When advocating to fight stigma and promote acceptance of neurodivergent individuals, the current debate on neurodiversity does not present a major challenge to psychiatric theory and research. The controversy arises when neurodiversity is taken to its extreme, denying the existence of neurodevelopmental disorders. Evolutionary psychiatry has recently contributed to the neurodiversity debate by providing adaptive explanations. These explanations are based on the unproven assumption that neurodiversity has been shaped by natural selection, as some atypical neurocognitive profiles increased inclusive fitness in the ancestral environment. Evolutionary psychiatry recognizes the heterogeneity of neurodiversity, acknowledges the existence of neurodevelopmental disorders, and establishes fitness disadvantage as the criterion of morbidity. The evolutionary definition of pathological neurodiversity is based on an objective criterion but it has limited utility in clinical practice. Cultural relativism has always played a role in the history of medicine and psychiatry, often overshadowing scientific analysis. Therapeutic concerns are influenced by cultural trends that can lean towards either medicalization or diagnostic nihilism.