>>19374091I think it has to do with the artist's desired focal point. Old statues are notable for their exaggerated proportions, superhero physiques and shit. If we're talking thinkers, warriors, and heroes, the focal point is the overall physique and stature of the person. This means that their proportions and musculature will be exaggerated to give that awe inspiring effect. Inversely, there's the sexual aspect of a nude figure. My first idea is that by making the penis smaller, the rest of the body feels proportionally larger. I also think that it could be due to the desired effect of a statue. These were created as morale boosters and as part of culture, not as sexual markers or true representatives of regular people. If the sexual organ was larger, it would take away from the super proportions of the figure and distract from the purpose, since people are monkey brain and are drawn to sexuality. The statues reduce sexual draw and increase the positive proportions according to the purpose simultaneously.